diff --git a/.dockerignore b/.dockerignore
index 10321c48..9514a1bf 100644
--- a/.dockerignore
+++ b/.dockerignore
@@ -1,8 +1,15 @@
 .git
 .github
 .gradle
+.env
+secrets
 build
 out
+logs
+load-testing/results/
+*.jfr
+*.hprof
+gc.log*
 *.iml
 .idea
 **/.DS_Store
diff --git a/.github/workflows/cicd.yml b/.github/workflows/cicd.yml
index 620ddb46..d5a6a932 100644
--- a/.github/workflows/cicd.yml
+++ b/.github/workflows/cicd.yml
@@ -1,4 +1,7 @@
 # CI/CD에 필요한 GitHub Secrets (Repo Settings > Secrets and variables > Actions)
+# - Docker Hub: DOCKERHUB_USERNAME, DOCKERHUB_TOKEN
+# - Server: SERVER_HOST, SERVER_USER, SERVER_SSH_KEY, SERVER_SSH_PORT
+# - GitHub repo/submodule access: GITHUB_TOKEN
 
 name: cicd
 
@@ -40,8 +43,8 @@ jobs:
 
       - name: Run tests
         run: |
-          echo ">>> [CI] Running tests..."
-          ./gradlew test --no-daemon
+          echo ">>> [CI] Running tests without integration tests..."
+          ./gradlew test -PskipIntegrationTests --no-daemon
           echo ">>> [CI] Tests passed"
 
   docker-build-and-push:
@@ -118,18 +121,6 @@ jobs:
           IMAGE: ${{ secrets.DOCKERHUB_USERNAME }}/dorumdorum-be:pinpoint
           DOCKERHUB_USERNAME: ${{ secrets.DOCKERHUB_USERNAME }}
           DOCKERHUB_TOKEN: ${{ secrets.DOCKERHUB_TOKEN }}
-          FIREBASE_SERVICE_ACCOUNT_B64: ${{ secrets.FIREBASE_SERVICE_ACCOUNT_B64 }}
-          RDB_USERNAME: ${{ secrets.RDB_USERNAME }}
-          RDB_URL: ${{ secrets.RDB_URL }}
-          RDB_PASSWORD: ${{ secrets.RDB_PASSWORD }}
-          MYSQL_ROOT_PASSWORD: ${{ secrets.MYSQL_ROOT_PASSWORD }}
-          MYSQL_DATABASE: ${{ secrets.MYSQL_DATABASE }}
-          JWT_KEY: ${{ secrets.JWT_KEY }}
-          JWT_ACCESS_EXPIRATION: ${{ secrets.JWT_ACCESS_EXPIRATION }}
-          JWT_REFRESH_EXPIRATION: ${{ secrets.JWT_REFRESH_EXPIRATION }}
-          SMTP_USERNAME: ${{ secrets.SMTP_USERNAME }}
-          SMTP_PASSWORD: ${{ secrets.SMTP_PASSWORD }}
-          DISCORD_WEBHOOK: ${{ secrets.DISCORD_WEBHOOK }}
           CONTAINER_NAME: dorumdorum-be
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           REPO_FULL_NAME: ${{ github.repository }}
@@ -138,56 +129,11 @@ jobs:
           username: ${{ secrets.SERVER_USER }}
           key: ${{ secrets.SERVER_SSH_KEY }}
           port: ${{ secrets.SERVER_SSH_PORT }}
-          envs: IMAGE,DOCKERHUB_USERNAME,DOCKERHUB_TOKEN,FIREBASE_SERVICE_ACCOUNT_B64,RDB_USERNAME,RDB_URL,RDB_PASSWORD,MYSQL_ROOT_PASSWORD,MYSQL_DATABASE,JWT_KEY,JWT_ACCESS_EXPIRATION,JWT_REFRESH_EXPIRATION,SMTP_USERNAME,SMTP_PASSWORD,CONTAINER_NAME,GITHUB_TOKEN,REPO_FULL_NAME,DISCORD_WEBHOOK
+          envs: IMAGE,DOCKERHUB_USERNAME,DOCKERHUB_TOKEN,CONTAINER_NAME,GITHUB_TOKEN,REPO_FULL_NAME
           script_stop: true
           script: |
             set -e
-            echo ">>> [Deploy] SSH 연결됨, 환경 변수 정규화 중..."
-
-            RDB_USERNAME="$(printf '%s' "$RDB_USERNAME" | tr -d '\r\n')"
-            RDB_URL="$(printf '%s' "$RDB_URL" | tr -d '\r\n')"
-            RDB_PASSWORD="$(printf '%s' "$RDB_PASSWORD" | tr -d '\r\n')"
-            MYSQL_ROOT_PASSWORD="$(printf '%s' "$MYSQL_ROOT_PASSWORD" | tr -d '\r\n')"
-            MYSQL_DATABASE="$(printf '%s' "$MYSQL_DATABASE" | tr -d '\r\n')"
-            JWT_KEY="$(printf '%s' "$JWT_KEY" | tr -d '\r\n')"
-            JWT_ACCESS_EXPIRATION="$(printf '%s' "$JWT_ACCESS_EXPIRATION" | tr -d '\r\n')"
-            JWT_REFRESH_EXPIRATION="$(printf '%s' "$JWT_REFRESH_EXPIRATION" | tr -d '\r\n')"
-            SMTP_USERNAME="$(printf '%s' "$SMTP_USERNAME" | tr -d '\r\n')"
-            SMTP_PASSWORD="$(printf '%s' "$SMTP_PASSWORD" | tr -d '\r\n')"
-
-            DEPLOY_PATH="${HOME}/dorumdorum"
-            mkdir -p "$DEPLOY_PATH"
-            cd "$DEPLOY_PATH"
-            echo ">>> [Deploy] DEPLOY_PATH=$DEPLOY_PATH"
-
-            # 1) Firebase 서비스 계정 파일 생성 (VM에 저장)
-            printf '%s' "$FIREBASE_SERVICE_ACCOUNT_B64" | base64 -d > firebase-service-account.json
-            chmod 600 firebase-service-account.json
-
-            # 2) 컨테이너에서 참조할 경로를 env로 고정
-            FIREBASE_SERVICE_ACCOUNT_PATH="/app/firebase-service-account.json"
-
-            # 3) .env 생성
-            # Pinpoint Web reads Spring datasource keys directly.
-            printf '%s\n' \
-              "SPRING_PROFILES_ACTIVE=prod" \
-              "RDB_USERNAME=$RDB_USERNAME" \
-              "RDB_URL=$RDB_URL" \
-              "RDB_PASSWORD=$RDB_PASSWORD" \
-              "MYSQL_ROOT_PASSWORD=$MYSQL_ROOT_PASSWORD" \
-              "MYSQL_DATABASE=$MYSQL_DATABASE" \
-              "SPRING_DATASOURCE_URL=$RDB_URL" \
-              "SPRING_DATASOURCE_USERNAME=$RDB_USERNAME" \
-              "SPRING_DATASOURCE_PASSWORD=$RDB_PASSWORD" \
-              "JWT_KEY=$JWT_KEY" \
-              "JWT_ACCESS_EXPIRATION=$JWT_ACCESS_EXPIRATION" \
-              "JWT_REFRESH_EXPIRATION=$JWT_REFRESH_EXPIRATION" \
-              "SMTP_USERNAME=$SMTP_USERNAME" \
-              "SMTP_PASSWORD=$SMTP_PASSWORD" \
-              "DISCORD_WEBHOOK=$DISCORD_WEBHOOK" \
-              "FIREBASE_SERVICE_ACCOUNT_PATH=$FIREBASE_SERVICE_ACCOUNT_PATH" > .env
-            chmod 600 .env
-            echo ">>> [Deploy] .env, firebase-service-account.json 생성 완료"
+            echo ">>> [Deploy] SSH 연결됨"
 
             docker info >/dev/null 2>&1 || {
               echo "Docker socket permission denied for current deploy user."
@@ -198,8 +144,8 @@ jobs:
             echo "$DOCKERHUB_TOKEN" | docker login -u "$DOCKERHUB_USERNAME" --password-stdin
             echo ">>> [Deploy] Docker Hub 로그인 완료"
 
-            echo ">>> [Deploy] MySQL 이미지 pull 중..."
-            docker pull mysql:8.0
+            echo ">>> [Deploy] PostgreSQL 이미지 pull 중..."
+            docker pull postgres:16-alpine
             echo ">>> [Deploy] Redis 이미지 pull 중..."
             docker pull redis:7-alpine
             echo ">>> [Deploy] Backend 이미지 pull 중..."
@@ -215,9 +161,14 @@ jobs:
             echo ">>> [Deploy] COMPOSE_PATH=$COMPOSE_PATH, Git clone 중..."
             rm -rf temp_repo
 
-            # Git에서 production 브랜치로 docker-compose.yml, monitoring 가져오기
+            # Git에서 production 브랜치로 docker-compose.yml, monitoring, secrets submodule 가져오기
             git clone --depth 1 -b production "https://x-access-token:${GITHUB_TOKEN}@github.com/${REPO_FULL_NAME}.git" temp_repo
-            echo ">>> [Deploy] Clone 완료, docker-compose.yml · monitoring 복사 중..."
+            (
+              cd temp_repo
+              git -c url."https://x-access-token:${GITHUB_TOKEN}@github.com/".insteadOf="https://github.com/" \
+                submodule update --init --recursive --depth 1
+            )
+            echo ">>> [Deploy] Clone 완료, docker-compose.yml · monitoring · secrets 복사 중..."
             
             if [ -f "temp_repo/BE/docker-compose.yml" ]; then
               cp temp_repo/BE/docker-compose.yml .
@@ -248,6 +199,19 @@ jobs:
               mkdir -p monitoring/prometheus monitoring/grafana/provisioning/dashboards/json monitoring/grafana/provisioning/datasources
             fi
 
+            rm -rf secrets
+            if [ -d "temp_repo/BE/secrets" ]; then
+              cp -R temp_repo/BE/secrets .
+              echo ">>> [Deploy] BE/secrets 복사 완료"
+            elif [ -d "temp_repo/secrets" ]; then
+              cp -R temp_repo/secrets .
+              echo ">>> [Deploy] secrets 복사 완료"
+            else
+              echo "ERROR: secrets submodule directory not found in temp_repo/"
+              exit 1
+            fi
+            chmod 600 secrets/.env secrets/firebase-service-account.json
+
             rm -rf temp_repo
             echo ">>> [Deploy] temp_repo 삭제, compose 파일 확인 중..."
 
@@ -257,21 +221,23 @@ jobs:
               ls -la
               exit 1
             fi
-            
-            # .env 파일과 firebase-service-account.json 복사
-            cp "$DEPLOY_PATH/.env" .
-            cp "$DEPLOY_PATH/firebase-service-account.json" .
-            echo ">>> [Deploy] .env, firebase-service-account.json 복사 완료"
+
+            if [ ! -f "secrets/.env" ] || [ ! -f "secrets/firebase-service-account.json" ]; then
+              echo "ERROR: required secret files are missing"
+              ls -la secrets || true
+              exit 1
+            fi
 
             # docker-compose로 모든 서비스 실행
             export BACKEND_IMAGE="$IMAGE"
             export CONTAINER_NAME="$CONTAINER_NAME"
+            COMPOSE="docker compose --env-file secrets/.env -f docker-compose.yml"
             echo ">>> [Deploy] 기존 컨테이너 정리 (down + 이름으로 강제 제거)..."
-            docker compose -f docker-compose.yml down --remove-orphans >/dev/null 2>&1 || true
+            $COMPOSE down --remove-orphans >/dev/null 2>&1 || true
             docker rm -f dorumdorum-redis dorumdorum-be dorumdorum-prometheus dorumdorum-grafana zoo1 pinpoint-hbase pinpoint-collector pinpoint-web 2>/dev/null || true
 
             echo ">>> [Deploy] [1/6] ZooKeeper 기동..."
-            docker compose -f docker-compose.yml up -d zoo1
+            $COMPOSE up -d zoo1
             for i in $(seq 1 30); do
               if docker ps --format '{{.Names}}' | grep -q '^zoo1$'; then
                 echo ">>> [Deploy] ZooKeeper up"
@@ -281,7 +247,7 @@ jobs:
             done
 
             echo ">>> [Deploy] [2/6] HBase 기동..."
-            docker compose -f docker-compose.yml up -d pinpoint-hbase
+            $COMPOSE up -d pinpoint-hbase
             echo ">>> [Deploy] HBase 초기화 대기..."
             HBASE_READY=0
             for i in $(seq 1 300); do
@@ -305,7 +271,7 @@ jobs:
             fi
 
             echo ">>> [Deploy] [3/6] Pinpoint Collector 기동..."
-            docker compose -f docker-compose.yml up -d pinpoint-collector
+            $COMPOSE up -d pinpoint-collector
             COLLECTOR_READY=0
             for i in $(seq 1 60); do
               if docker logs pinpoint-collector 2>&1 | grep -Eq "Started .*CollectorApp|Started CollectorApp"; then
@@ -322,7 +288,7 @@ jobs:
             fi
 
             echo ">>> [Deploy] [4/6] Pinpoint Web 기동..."
-            docker compose -f docker-compose.yml up -d pinpoint-web
+            $COMPOSE up -d pinpoint-web
             WEB_READY=0
             for i in $(seq 1 60); do
               if docker logs pinpoint-web 2>&1 | grep -Eq "Started .*WebApp|Started WebApp|Started .*PinpointWebApplication"; then
@@ -339,10 +305,10 @@ jobs:
             fi
 
             echo ">>> [Deploy] [5/6] Backend 기동..."
-            docker compose -f docker-compose.yml up -d backend
+            $COMPOSE up -d backend
 
             echo ">>> [Deploy] [6/6] Redis/Monitoring 기동..."
-            docker compose -f docker-compose.yml up -d redis prometheus grafana
+            $COMPOSE up -d redis prometheus grafana
 
             echo ">>> [Deploy] 오래된 이미지 정리 중..."
             docker image prune -af --filter "until=168h"
diff --git a/.gitignore b/.gitignore
index a311993f..7534d640 100644
--- a/.gitignore
+++ b/.gitignore
@@ -55,7 +55,16 @@ pinpoint-agent/tools/
 .env
 /analysis/
 
+### JVM profiling artifacts ###
+logs/
+*.jfr
+*.hprof
+gc.log*
+
+### k6 load test artifacts ###
+load-testing/results/
+
 # macOS artefacts
 .DS_Store
 
-docs/
\ No newline at end of file
+docs/
diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 00000000..392a0f4e
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "secrets"]
+	path = secrets
+	url = https://github.com/DorumDorum/secrets
diff --git a/Dockerfile b/Dockerfile
index 83d51c1e..6daa913c 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -15,6 +15,8 @@ WORKDIR /app
 
 COPY --from=builder /app/build/libs/*.jar app.jar
 
+RUN mkdir -p /app/logs/jfr
+
 EXPOSE 8080
 
-ENTRYPOINT ["sh", "-c", "exec java ${JAVA_OPTS} -Dspring.profiles.active=${SPRING_PROFILES_ACTIVE:-prod} -jar /app/app.jar"]
+ENTRYPOINT ["sh", "-c", "DEFAULT_JAVA_OPTS=\"-XX:StartFlightRecording=name=dorumdorum,settings=${JFR_SETTINGS:-profile},disk=true,dumponexit=true,filename=/app/logs/jfr/dorumdorum-${JFR_RUN_ID:-cloud-load-test}.jfr,maxage=${JFR_MAX_AGE:-30m},maxsize=${JFR_MAX_SIZE:-512m}\"; EFFECTIVE_JAVA_OPTS=\"${DEFAULT_JAVA_OPTS} ${JAVA_OPTS:-}\"; exec java ${EFFECTIVE_JAVA_OPTS} -Dspring.profiles.active=${SPRING_PROFILES_ACTIVE:-prod} -jar /app/app.jar"]
diff --git a/Dockerfile.pinpoint b/Dockerfile.pinpoint
index ccbffc8e..ca7d9574 100644
--- a/Dockerfile.pinpoint
+++ b/Dockerfile.pinpoint
@@ -28,6 +28,8 @@ WORKDIR /app
 COPY --from=builder /app/build/libs/*.jar app.jar
 COPY --from=builder /app/pinpoint-agent /app/pinpoint-agent
 
+RUN mkdir -p /app/logs/jfr
+
 # Pinpoint Agent JVM 옵션 (환경변수로 Collector IP 등 오버라이드 가능)
 ENV PINPOINT_VERSION=2.5.4
 ENV PINPOINT_COLLECTOR_IP=pinpoint-collector
@@ -38,12 +40,12 @@ EXPOSE 8080
 
 # pinpoint-root.config에서 Collector IP 오버라이드 (profiler.transport.grpc.collector.ip)
 # -D 옵션으로 전달
-ENTRYPOINT ["sh", "-c", "java \
+ENTRYPOINT ["sh", "-c", "DEFAULT_JAVA_OPTS=\"-XX:StartFlightRecording=name=dorumdorum,settings=${JFR_SETTINGS:-profile},disk=true,dumponexit=true,filename=/app/logs/jfr/dorumdorum-${JFR_RUN_ID:-cloud-load-test}.jfr,maxage=${JFR_MAX_AGE:-30m},maxsize=${JFR_MAX_SIZE:-512m}\"; EFFECTIVE_JAVA_OPTS=\"${DEFAULT_JAVA_OPTS} ${JAVA_OPTS:-}\"; exec java \
   -javaagent:/app/pinpoint-agent/pinpoint-bootstrap-${PINPOINT_VERSION}.jar \
   -Dpinpoint.agentId=${PINPOINT_AGENT_ID} \
   -Dpinpoint.applicationName=${PINPOINT_APPLICATION_NAME} \
   -Dprofiler.transport.grpc.collector.ip=${PINPOINT_COLLECTOR_IP} \
   -Dpinpoint.container=true \
-  ${JAVA_OPTS} \
+  ${EFFECTIVE_JAVA_OPTS} \
   -Dspring.profiles.active=${SPRING_PROFILES_ACTIVE:-prod} \
   -jar /app/app.jar"]
diff --git a/build.gradle b/build.gradle
index d4ff20ba..574ce83b 100644
--- a/build.gradle
+++ b/build.gradle
@@ -94,6 +94,10 @@ dependencies {
 
 tasks.named('test') {
     useJUnitPlatform()
+
+    if (project.hasProperty('skipIntegrationTests')) {
+        exclude '**/*IntegrationTest.class'
+    }
 }
 
 def generated = "$buildDir/generated/sources/annotationProcessor/java/main"
diff --git a/docker-compose.yml b/docker-compose.yml
index bf88b1fe..ecb6ada4 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -38,16 +38,19 @@ services:
       - "8080:8080"
     stop_grace_period: 45s
     env_file:
-      - .env
+      - ./secrets/.env
     environment:
       - REDIS_HOST=redis
       - REDIS_PORT=6379
       - PINPOINT_COLLECTOR_IP=pinpoint-collector
       - PINPOINT_APPLICATION_NAME=dorumdorum
-      - PINPOINT_AGENT_ID=${PINPOINT_AGENT_ID:-dorumdorum-backend-${HOSTNAME}}
+      - PINPOINT_AGENT_ID=${PINPOINT_AGENT_ID:-dorumdorum-backend-local}
       - PINPOINT_AGENT_NAME=${PINPOINT_AGENT_NAME:-dorumdorum-be}
+      - JAVA_OPTS=-Xms6g -Xmx6g -XX:+UseG1GC -XX:MaxGCPauseMillis=200 -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=/var/log -XX:+ExitOnOutOfMemoryError -Xlog:gc*,safepoint:file=/var/log/gc.log:time,uptime,level,tags:filecount=10,filesize=50m
     volumes:
-      - ./firebase-service-account.json:/app/firebase-service-account.json:ro
+      - ./secrets/firebase-service-account.json:/app/firebase-service-account.json:ro
+      - gc_logs:/var/log
+      - ./logs/jfr:/app/logs/jfr
     depends_on:
       postgres:
         condition: service_healthy
@@ -55,11 +58,8 @@ services:
         condition: service_started
       pinpoint-collector:
         condition: service_started
-    deploy:
-      resources:
-        limits:
-          cpus: "4.0"
-          memory: 16G
+    mem_limit: 8G
+    cpus: 2.0
     restart: unless-stopped
     networks:
       - dorumdorum-net
@@ -122,7 +122,7 @@ services:
     image: pinpointdocker/pinpoint-web:2.5.4
     container_name: pinpoint-web
     env_file:
-      - .env
+      - ./secrets/.env
     depends_on:
       - pinpoint-hbase
     networks:
@@ -144,7 +144,7 @@ services:
     image: prom/prometheus:v2.52.0
     container_name: dorumdorum-prometheus
     ports:
-      - "9090:9090"
+      - "127.0.0.1:9090:9090"
     volumes:
       - ./monitoring/prometheus/prometheus.prod.yml:/etc/prometheus/prometheus.yml:ro
       - prometheus_data:/prometheus
@@ -152,12 +152,38 @@ services:
       - "--config.file=/etc/prometheus/prometheus.yml"
       - "--storage.tsdb.path=/prometheus"
       - "--web.enable-lifecycle"
+      - "--web.enable-remote-write-receiver"
     extra_hosts:
       - "host.docker.internal:host-gateway"
     restart: unless-stopped
     networks:
       - dorumdorum-net
 
+  k6:
+    image: ${K6_IMAGE:-grafana/k6:latest}
+    container_name: dorumdorum-k6
+    profiles:
+      - loadtest
+    environment:
+      - BASE_URL=${K6_BASE_URL:-http://backend:8080}
+      - K6_OUT=${K6_OUT:-experimental-prometheus-rw}
+      - K6_PROMETHEUS_RW_SERVER_URL=${K6_PROMETHEUS_RW_SERVER_URL:-http://prometheus:9090/api/v1/write}
+      - K6_PROMETHEUS_RW_PUSH_INTERVAL=${K6_PROMETHEUS_RW_PUSH_INTERVAL:-5s}
+      - K6_PROMETHEUS_RW_TREND_STATS=${K6_PROMETHEUS_RW_TREND_STATS:-p(90),p(95),p(99),min,max,avg}
+      - K6_PROMETHEUS_RW_STALE_MARKERS=${K6_PROMETHEUS_RW_STALE_MARKERS:-true}
+      - K6_WEB_DASHBOARD=${K6_WEB_DASHBOARD:-true}
+      - K6_WEB_DASHBOARD_EXPORT=${K6_WEB_DASHBOARD_EXPORT:-/results/k6-report.html}
+    volumes:
+      - ./load-testing/k6:/scripts:ro
+      - ./load-testing/results:/results
+    working_dir: /scripts
+    entrypoint: ["k6"]
+    depends_on:
+      - backend
+      - prometheus
+    networks:
+      - dorumdorum-net
+
   grafana:
     image: grafana/grafana:11.2.0
     container_name: dorumdorum-grafana
@@ -185,6 +211,7 @@ volumes:
   grafana_data:
   hbase_data:
   zookeeper_data:
+  gc_logs:
 
 networks:
   dorumdorum-net:
diff --git a/load-testing/README.md b/load-testing/README.md
new file mode 100644
index 00000000..026fd456
--- /dev/null
+++ b/load-testing/README.md
@@ -0,0 +1,16 @@
+# k6 Load Testing
+
+This directory is reserved for k6 load-test assets. Test scripts are intentionally not included.
+
+Place scripts under `load-testing/k6/` when needed, then run:
+
+```sh
+docker compose --profile loadtest run --rm k6 run --tag testid=gc-baseline /scripts/<script>.js
+```
+
+Defaults:
+
+- The application target for scripts is exposed as `BASE_URL=http://backend:8080`.
+- k6 metrics are remote-written to Prometheus at `http://prometheus:9090/api/v1/write`.
+- The optional k6 web dashboard export path is `/results/k6-report.html`.
+- Use a different `testid` tag for each GC tuning experiment to separate runs in Prometheus/Grafana.
diff --git a/load-testing/k6/.gitkeep b/load-testing/k6/.gitkeep
new file mode 100644
index 00000000..8b137891
--- /dev/null
+++ b/load-testing/k6/.gitkeep
@@ -0,0 +1 @@
+
diff --git a/monitoring/grafana/provisioning/dashboards/json/k6-jvm-gc-load-test.json b/monitoring/grafana/provisioning/dashboards/json/k6-jvm-gc-load-test.json
new file mode 100644
index 00000000..481c3840
--- /dev/null
+++ b/monitoring/grafana/provisioning/dashboards/json/k6-jvm-gc-load-test.json
@@ -0,0 +1,776 @@
+{
+  "annotations": {
+    "list": []
+  },
+  "editable": true,
+  "fiscalYearStartMonth": 0,
+  "graphTooltip": 1,
+  "id": null,
+  "links": [],
+  "liveNow": false,
+  "panels": [
+    {
+      "datasource": {
+        "type": "prometheus",
+        "uid": "prometheus"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "color": {
+            "mode": "thresholds"
+          },
+          "mappings": [],
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              }
+            ]
+          },
+          "unit": "short"
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 6,
+        "x": 0,
+        "y": 0
+      },
+      "id": 1,
+      "options": {
+        "colorMode": "value",
+        "graphMode": "area",
+        "justifyMode": "auto",
+        "orientation": "auto",
+        "reduceOptions": {
+          "calcs": [
+            "lastNotNull"
+          ],
+          "fields": "",
+          "values": false
+        },
+        "textMode": "auto"
+      },
+      "targets": [
+        {
+          "expr": "sum(k6_vus{testid=~\"$testid\"}) or vector(0)",
+          "legendFormat": "active VUs",
+          "refId": "A"
+        }
+      ],
+      "title": "k6 Active VUs",
+      "type": "stat"
+    },
+    {
+      "datasource": {
+        "type": "prometheus",
+        "uid": "prometheus"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "color": {
+            "mode": "thresholds"
+          },
+          "mappings": [],
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              }
+            ]
+          },
+          "unit": "reqps"
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 6,
+        "x": 6,
+        "y": 0
+      },
+      "id": 2,
+      "options": {
+        "colorMode": "value",
+        "graphMode": "area",
+        "justifyMode": "auto",
+        "orientation": "auto",
+        "reduceOptions": {
+          "calcs": [
+            "lastNotNull"
+          ],
+          "fields": "",
+          "values": false
+        },
+        "textMode": "auto"
+      },
+      "targets": [
+        {
+          "expr": "sum(rate(k6_http_reqs_total{testid=~\"$testid\"}[1m])) or vector(0)",
+          "legendFormat": "k6 RPS",
+          "refId": "A"
+        }
+      ],
+      "title": "k6 Request Rate",
+      "type": "stat"
+    },
+    {
+      "datasource": {
+        "type": "prometheus",
+        "uid": "prometheus"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "color": {
+            "mode": "thresholds"
+          },
+          "mappings": [],
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              },
+              {
+                "color": "yellow",
+                "value": 0.01
+              },
+              {
+                "color": "red",
+                "value": 0.05
+              }
+            ]
+          },
+          "unit": "percentunit"
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 6,
+        "x": 12,
+        "y": 0
+      },
+      "id": 3,
+      "options": {
+        "colorMode": "value",
+        "graphMode": "area",
+        "justifyMode": "auto",
+        "orientation": "auto",
+        "reduceOptions": {
+          "calcs": [
+            "lastNotNull"
+          ],
+          "fields": "",
+          "values": false
+        },
+        "textMode": "auto"
+      },
+      "targets": [
+        {
+          "expr": "avg(k6_http_req_failed_rate{testid=~\"$testid\"}) or vector(0)",
+          "legendFormat": "failed",
+          "refId": "A"
+        }
+      ],
+      "title": "k6 Failure Rate",
+      "type": "stat"
+    },
+    {
+      "datasource": {
+        "type": "prometheus",
+        "uid": "prometheus"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "color": {
+            "mode": "thresholds"
+          },
+          "mappings": [],
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              },
+              {
+                "color": "yellow",
+                "value": 0.7
+              },
+              {
+                "color": "red",
+                "value": 0.9
+              }
+            ]
+          },
+          "unit": "percentunit"
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 6,
+        "x": 18,
+        "y": 0
+      },
+      "id": 4,
+      "options": {
+        "colorMode": "value",
+        "graphMode": "area",
+        "justifyMode": "auto",
+        "orientation": "auto",
+        "reduceOptions": {
+          "calcs": [
+            "lastNotNull"
+          ],
+          "fields": "",
+          "values": false
+        },
+        "textMode": "auto"
+      },
+      "targets": [
+        {
+          "expr": "sum(jvm_memory_used_bytes{application=\"dorumdorum\",area=\"heap\"}) / sum(jvm_memory_max_bytes{application=\"dorumdorum\",area=\"heap\"})",
+          "legendFormat": "heap usage",
+          "refId": "A"
+        }
+      ],
+      "title": "JVM Heap Usage",
+      "type": "stat"
+    },
+    {
+      "datasource": {
+        "type": "prometheus",
+        "uid": "prometheus"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "color": {
+            "mode": "palette-classic"
+          },
+          "custom": {
+            "drawStyle": "line",
+            "fillOpacity": 10,
+            "lineInterpolation": "linear",
+            "lineWidth": 1,
+            "pointSize": 5,
+            "showPoints": "never",
+            "spanNulls": false
+          },
+          "mappings": [],
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              }
+            ]
+          },
+          "unit": "short"
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 7,
+        "w": 8,
+        "x": 0,
+        "y": 4
+      },
+      "id": 5,
+      "options": {
+        "legend": {
+          "displayMode": "list",
+          "placement": "bottom",
+          "showLegend": true
+        },
+        "tooltip": {
+          "mode": "multi",
+          "sort": "none"
+        }
+      },
+      "targets": [
+        {
+          "expr": "sum(k6_vus{testid=~\"$testid\"}) or vector(0)",
+          "legendFormat": "active VUs",
+          "refId": "A"
+        },
+        {
+          "expr": "sum(k6_vus_max{testid=~\"$testid\"}) or vector(0)",
+          "legendFormat": "max VUs",
+          "refId": "B"
+        }
+      ],
+      "title": "k6 VUs",
+      "type": "timeseries"
+    },
+    {
+      "datasource": {
+        "type": "prometheus",
+        "uid": "prometheus"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "color": {
+            "mode": "palette-classic"
+          },
+          "custom": {
+            "drawStyle": "line",
+            "fillOpacity": 10,
+            "lineInterpolation": "linear",
+            "lineWidth": 1,
+            "pointSize": 5,
+            "showPoints": "never",
+            "spanNulls": false
+          },
+          "mappings": [],
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              }
+            ]
+          },
+          "unit": "reqps"
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 7,
+        "w": 8,
+        "x": 8,
+        "y": 4
+      },
+      "id": 6,
+      "options": {
+        "legend": {
+          "displayMode": "list",
+          "placement": "bottom",
+          "showLegend": true
+        },
+        "tooltip": {
+          "mode": "multi",
+          "sort": "none"
+        }
+      },
+      "targets": [
+        {
+          "expr": "sum(rate(k6_http_reqs_total{testid=~\"$testid\"}[1m])) or vector(0)",
+          "legendFormat": "k6 generated RPS",
+          "refId": "A"
+        },
+        {
+          "expr": "sum(rate(http_server_requests_seconds_count{application=\"dorumdorum\"}[1m])) or vector(0)",
+          "legendFormat": "backend handled RPS",
+          "refId": "B"
+        }
+      ],
+      "title": "Request Rate Comparison",
+      "type": "timeseries"
+    },
+    {
+      "datasource": {
+        "type": "prometheus",
+        "uid": "prometheus"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "color": {
+            "mode": "palette-classic"
+          },
+          "custom": {
+            "drawStyle": "line",
+            "fillOpacity": 10,
+            "lineInterpolation": "linear",
+            "lineWidth": 1,
+            "pointSize": 5,
+            "showPoints": "never",
+            "spanNulls": false
+          },
+          "mappings": [],
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              }
+            ]
+          },
+          "unit": "s"
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 7,
+        "w": 8,
+        "x": 16,
+        "y": 4
+      },
+      "id": 7,
+      "options": {
+        "legend": {
+          "displayMode": "list",
+          "placement": "bottom",
+          "showLegend": true
+        },
+        "tooltip": {
+          "mode": "multi",
+          "sort": "none"
+        }
+      },
+      "targets": [
+        {
+          "expr": "avg(k6_http_req_duration_seconds_p95{testid=~\"$testid\"}) or vector(0)",
+          "legendFormat": "k6 p95",
+          "refId": "A"
+        },
+        {
+          "expr": "avg(k6_http_req_duration_seconds_p99{testid=~\"$testid\"}) or vector(0)",
+          "legendFormat": "k6 p99",
+          "refId": "B"
+        },
+        {
+          "expr": "histogram_quantile(0.95, sum(rate(http_server_requests_seconds_bucket{application=\"dorumdorum\"}[5m])) by (le))",
+          "legendFormat": "backend p95",
+          "refId": "C"
+        }
+      ],
+      "title": "Latency",
+      "type": "timeseries"
+    },
+    {
+      "datasource": {
+        "type": "prometheus",
+        "uid": "prometheus"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "color": {
+            "mode": "palette-classic"
+          },
+          "custom": {
+            "drawStyle": "line",
+            "fillOpacity": 10,
+            "lineInterpolation": "linear",
+            "lineWidth": 1,
+            "pointSize": 5,
+            "showPoints": "never",
+            "spanNulls": false
+          },
+          "mappings": [],
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              }
+            ]
+          },
+          "unit": "bytes"
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 8,
+        "w": 12,
+        "x": 0,
+        "y": 11
+      },
+      "id": 8,
+      "options": {
+        "legend": {
+          "displayMode": "list",
+          "placement": "bottom",
+          "showLegend": true
+        },
+        "tooltip": {
+          "mode": "multi",
+          "sort": "none"
+        }
+      },
+      "targets": [
+        {
+          "expr": "jvm_memory_used_bytes{application=\"dorumdorum\",area=\"heap\"}",
+          "legendFormat": "used {{id}}",
+          "refId": "A"
+        },
+        {
+          "expr": "jvm_memory_committed_bytes{application=\"dorumdorum\",area=\"heap\"}",
+          "legendFormat": "committed {{id}}",
+          "refId": "B"
+        },
+        {
+          "expr": "jvm_memory_max_bytes{application=\"dorumdorum\",area=\"heap\"}",
+          "legendFormat": "max {{id}}",
+          "refId": "C"
+        }
+      ],
+      "title": "JVM Heap",
+      "type": "timeseries"
+    },
+    {
+      "datasource": {
+        "type": "prometheus",
+        "uid": "prometheus"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "color": {
+            "mode": "palette-classic"
+          },
+          "custom": {
+            "drawStyle": "line",
+            "fillOpacity": 10,
+            "lineInterpolation": "linear",
+            "lineWidth": 1,
+            "pointSize": 5,
+            "showPoints": "never",
+            "spanNulls": false
+          },
+          "mappings": [],
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              }
+            ]
+          },
+          "unit": "s"
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 8,
+        "w": 12,
+        "x": 12,
+        "y": 11
+      },
+      "id": 9,
+      "options": {
+        "legend": {
+          "displayMode": "list",
+          "placement": "bottom",
+          "showLegend": true
+        },
+        "tooltip": {
+          "mode": "multi",
+          "sort": "none"
+        }
+      },
+      "targets": [
+        {
+          "expr": "rate(jvm_gc_pause_seconds_sum{application=\"dorumdorum\"}[1m])",
+          "legendFormat": "pause seconds/sec {{gc}} {{action}}",
+          "refId": "A"
+        },
+        {
+          "expr": "rate(jvm_gc_pause_seconds_count{application=\"dorumdorum\"}[1m])",
+          "legendFormat": "pause count/sec {{gc}} {{action}}",
+          "refId": "B"
+        }
+      ],
+      "title": "JVM GC Pause",
+      "type": "timeseries"
+    },
+    {
+      "datasource": {
+        "type": "prometheus",
+        "uid": "prometheus"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "color": {
+            "mode": "palette-classic"
+          },
+          "custom": {
+            "drawStyle": "line",
+            "fillOpacity": 10,
+            "lineInterpolation": "linear",
+            "lineWidth": 1,
+            "pointSize": 5,
+            "showPoints": "never",
+            "spanNulls": false
+          },
+          "mappings": [],
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              }
+            ]
+          },
+          "unit": "percentunit"
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 8,
+        "w": 12,
+        "x": 0,
+        "y": 19
+      },
+      "id": 10,
+      "options": {
+        "legend": {
+          "displayMode": "list",
+          "placement": "bottom",
+          "showLegend": true
+        },
+        "tooltip": {
+          "mode": "multi",
+          "sort": "none"
+        }
+      },
+      "targets": [
+        {
+          "expr": "process_cpu_usage{application=\"dorumdorum\"}",
+          "legendFormat": "process CPU",
+          "refId": "A"
+        },
+        {
+          "expr": "system_cpu_usage{application=\"dorumdorum\"}",
+          "legendFormat": "system CPU",
+          "refId": "B"
+        }
+      ],
+      "title": "JVM CPU Usage",
+      "type": "timeseries"
+    },
+    {
+      "datasource": {
+        "type": "prometheus",
+        "uid": "prometheus"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "color": {
+            "mode": "palette-classic"
+          },
+          "custom": {
+            "drawStyle": "line",
+            "fillOpacity": 10,
+            "lineInterpolation": "linear",
+            "lineWidth": 1,
+            "pointSize": 5,
+            "showPoints": "never",
+            "spanNulls": false
+          },
+          "mappings": [],
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              }
+            ]
+          },
+          "unit": "short"
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 8,
+        "w": 12,
+        "x": 12,
+        "y": 19
+      },
+      "id": 11,
+      "options": {
+        "legend": {
+          "displayMode": "list",
+          "placement": "bottom",
+          "showLegend": true
+        },
+        "tooltip": {
+          "mode": "multi",
+          "sort": "none"
+        }
+      },
+      "targets": [
+        {
+          "expr": "jvm_threads_live_threads{application=\"dorumdorum\"}",
+          "legendFormat": "live",
+          "refId": "A"
+        },
+        {
+          "expr": "jvm_threads_daemon_threads{application=\"dorumdorum\"}",
+          "legendFormat": "daemon",
+          "refId": "B"
+        },
+        {
+          "expr": "jvm_threads_peak_threads{application=\"dorumdorum\"}",
+          "legendFormat": "peak",
+          "refId": "C"
+        }
+      ],
+      "title": "JVM Threads",
+      "type": "timeseries"
+    }
+  ],
+  "refresh": "5s",
+  "schemaVersion": 39,
+  "tags": [
+    "dorumdorum",
+    "k6",
+    "jvm",
+    "gc"
+  ],
+  "templating": {
+    "list": [
+      {
+        "allValue": ".*",
+        "current": {
+          "selected": true,
+          "text": "All",
+          "value": "$__all"
+        },
+        "datasource": {
+          "type": "prometheus",
+          "uid": "prometheus"
+        },
+        "definition": "label_values(k6_http_reqs_total, testid)",
+        "hide": 0,
+        "includeAll": true,
+        "label": "testid",
+        "multi": true,
+        "name": "testid",
+        "options": [],
+        "query": {
+          "query": "label_values(k6_http_reqs_total, testid)",
+          "refId": "PrometheusVariableQueryEditor-VariableQuery"
+        },
+        "refresh": 1,
+        "regex": "",
+        "skipUrlSync": false,
+        "sort": 1,
+        "type": "query"
+      }
+    ]
+  },
+  "time": {
+    "from": "now-30m",
+    "to": "now"
+  },
+  "timepicker": {},
+  "timezone": "browser",
+  "title": "k6 JVM GC Load Test",
+  "uid": "k6-jvm-gc-load-test",
+  "version": 1,
+  "weekStart": ""
+}
diff --git a/secrets b/secrets
new file mode 160000
index 00000000..f1891b54
--- /dev/null
+++ b/secrets
@@ -0,0 +1 @@
+Subproject commit f1891b54a9ecfdb4f8c4342e838835ab32e427b4
diff --git a/src/main/java/com/project/dorumdorum/domain/chat/domain/entity/ChatMessage.java b/src/main/java/com/project/dorumdorum/domain/chat/domain/entity/ChatMessage.java
index fd60f8f7..a7b13b08 100644
--- a/src/main/java/com/project/dorumdorum/domain/chat/domain/entity/ChatMessage.java
+++ b/src/main/java/com/project/dorumdorum/domain/chat/domain/entity/ChatMessage.java
@@ -4,12 +4,14 @@
 import io.hypersistence.utils.hibernate.id.Tsid;
 import jakarta.persistence.*;
 import lombok.*;
+import org.hibernate.annotations.SQLRestriction;
 
 @Entity
 @Getter
 @NoArgsConstructor(access = AccessLevel.PROTECTED)
 @AllArgsConstructor(access = AccessLevel.PROTECTED)
 @Builder
+@SQLRestriction("deleted_at is null")
 @Table(
     indexes = @Index(name = "idx_chat_message_room_created_message", columnList = "chat_room_no, created_at, message_no")
 )
diff --git a/src/main/java/com/project/dorumdorum/domain/chat/domain/entity/ChatRoom.java b/src/main/java/com/project/dorumdorum/domain/chat/domain/entity/ChatRoom.java
index 8b3da9fb..8ce081e6 100644
--- a/src/main/java/com/project/dorumdorum/domain/chat/domain/entity/ChatRoom.java
+++ b/src/main/java/com/project/dorumdorum/domain/chat/domain/entity/ChatRoom.java
@@ -10,10 +10,12 @@
 import jakarta.persistence.Index;
 import jakarta.persistence.Table;
 import lombok.*;
+import org.hibernate.annotations.SQLRestriction;
 
 import java.time.LocalDateTime;
 
 @Entity
+@SQLRestriction("deleted_at is null")
 @Table(
         indexes = {
                 @Index(name = "idx_chat_room_last_message_at", columnList = "last_message_at"),
diff --git a/src/main/java/com/project/dorumdorum/domain/chat/domain/entity/ChatRoomMember.java b/src/main/java/com/project/dorumdorum/domain/chat/domain/entity/ChatRoomMember.java
index 52c4631a..5d4d018d 100644
--- a/src/main/java/com/project/dorumdorum/domain/chat/domain/entity/ChatRoomMember.java
+++ b/src/main/java/com/project/dorumdorum/domain/chat/domain/entity/ChatRoomMember.java
@@ -4,6 +4,7 @@
 import io.hypersistence.utils.hibernate.id.Tsid;
 import jakarta.persistence.*;
 import lombok.*;
+import org.hibernate.annotations.SQLRestriction;
 
 import java.time.LocalDateTime;
 
@@ -12,14 +13,11 @@
 @NoArgsConstructor(access = AccessLevel.PROTECTED)
 @AllArgsConstructor(access = AccessLevel.PROTECTED)
 @Builder
+@SQLRestriction("deleted_at is null")
 @Table(
     indexes = {
         @Index(name = "idx_chat_room_member_user_room", columnList = "user_no, chat_room_no")
-    },
-    uniqueConstraints = @UniqueConstraint(
-        name = "uk_chat_room_member_room_user",
-        columnNames = {"chat_room_no", "user_no"}
-    )
+    }
 )
 public class ChatRoomMember extends BaseEntity {
 
diff --git a/src/main/java/com/project/dorumdorum/domain/chat/domain/repository/ChatMessageRepository.java b/src/main/java/com/project/dorumdorum/domain/chat/domain/repository/ChatMessageRepository.java
index f5bb086e..f4969662 100644
--- a/src/main/java/com/project/dorumdorum/domain/chat/domain/repository/ChatMessageRepository.java
+++ b/src/main/java/com/project/dorumdorum/domain/chat/domain/repository/ChatMessageRepository.java
@@ -20,7 +20,7 @@ int decreaseUnreadCount(@Param("chatRoomNo") String chatRoomNo,
                             @Param("fromTime") LocalDateTime fromTime,
                             @Param("userNo") String userNo);
 
-    @Modifying(clearAutomatically = true)
-    @Query("DELETE FROM ChatMessage m WHERE m.chatRoom.chatRoomNo = :chatRoomNo")
+    @Modifying(clearAutomatically = true, flushAutomatically = true)
+    @Query("UPDATE ChatMessage m SET m.deletedAt = CURRENT_TIMESTAMP WHERE m.chatRoom.chatRoomNo = :chatRoomNo AND m.deletedAt IS NULL")
     void deleteByChatRoomNo(@Param("chatRoomNo") String chatRoomNo);
 }
diff --git a/src/main/java/com/project/dorumdorum/domain/chat/domain/repository/ChatRoomMemberRepository.java b/src/main/java/com/project/dorumdorum/domain/chat/domain/repository/ChatRoomMemberRepository.java
index 8dbda33d..40821ad7 100644
--- a/src/main/java/com/project/dorumdorum/domain/chat/domain/repository/ChatRoomMemberRepository.java
+++ b/src/main/java/com/project/dorumdorum/domain/chat/domain/repository/ChatRoomMemberRepository.java
@@ -37,6 +37,6 @@ Optional<ChatRoomMember> findByChatRoomNoAndUserNoForUpdate(
     boolean existsByChatRoom_ChatRoomNoAndUserNo(String chatRoomNo, String userNo);
 
     @Modifying(clearAutomatically = true, flushAutomatically = true)
-    @Query("DELETE FROM ChatRoomMember m WHERE m.chatRoom = :chatRoom")
+    @Query("UPDATE ChatRoomMember m SET m.deletedAt = CURRENT_TIMESTAMP WHERE m.chatRoom = :chatRoom AND m.deletedAt IS NULL")
     void deleteAllByChatRoom(@Param("chatRoom") ChatRoom chatRoom);
 }
diff --git a/src/main/java/com/project/dorumdorum/domain/chat/domain/repository/ChatRoomRepository.java b/src/main/java/com/project/dorumdorum/domain/chat/domain/repository/ChatRoomRepository.java
index 0a2ad5ae..bd20de31 100644
--- a/src/main/java/com/project/dorumdorum/domain/chat/domain/repository/ChatRoomRepository.java
+++ b/src/main/java/com/project/dorumdorum/domain/chat/domain/repository/ChatRoomRepository.java
@@ -24,6 +24,6 @@ Optional<ChatRoom> findByRoomNoAndChatRoomTypeAndApplicantUserNo(
             String roomNo, ChatRoomType chatRoomType, String applicantUserNo);
 
     @Modifying(clearAutomatically = true, flushAutomatically = true)
-    @Query("DELETE FROM ChatRoom c WHERE c.chatRoomNo = :chatRoomNo")
+    @Query("UPDATE ChatRoom c SET c.deletedAt = CURRENT_TIMESTAMP WHERE c.chatRoomNo = :chatRoomNo AND c.deletedAt IS NULL")
     void deleteByChatRoomNo(@Param("chatRoomNo") String chatRoomNo);
 }
diff --git a/src/main/java/com/project/dorumdorum/domain/chat/domain/service/ChatRoomMemberService.java b/src/main/java/com/project/dorumdorum/domain/chat/domain/service/ChatRoomMemberService.java
index bf18bea2..8280a611 100644
--- a/src/main/java/com/project/dorumdorum/domain/chat/domain/service/ChatRoomMemberService.java
+++ b/src/main/java/com/project/dorumdorum/domain/chat/domain/service/ChatRoomMemberService.java
@@ -67,7 +67,8 @@ public boolean isMemberByChatRoomNo(String chatRoomNo, String userNo) {
     }
 
     public void leave(ChatRoomMember member) {
-        chatRoomMemberRepository.delete(member);
+        member.delete();
+        chatRoomMemberRepository.save(member);
     }
 
     public void deleteAllByChatRoom(ChatRoom chatRoom) {
diff --git a/src/main/java/com/project/dorumdorum/domain/chat/domain/service/ChatRoomService.java b/src/main/java/com/project/dorumdorum/domain/chat/domain/service/ChatRoomService.java
index d2573ad6..ac401ae0 100644
--- a/src/main/java/com/project/dorumdorum/domain/chat/domain/service/ChatRoomService.java
+++ b/src/main/java/com/project/dorumdorum/domain/chat/domain/service/ChatRoomService.java
@@ -64,7 +64,8 @@ public void updateLastMessage(ChatRoom chatRoom, String content, String senderNo
     }
 
     public void delete(ChatRoom chatRoom) {
-        chatRoomRepository.delete(chatRoom);
+        chatRoom.delete();
+        chatRoomRepository.save(chatRoom);
     }
 
     public void deleteByChatRoomNo(String chatRoomNo) {
diff --git a/src/main/java/com/project/dorumdorum/domain/checklist/domain/entity/ChecklistBase.java b/src/main/java/com/project/dorumdorum/domain/checklist/domain/entity/ChecklistBase.java
index 6aeb6f5a..becea0d8 100644
--- a/src/main/java/com/project/dorumdorum/domain/checklist/domain/entity/ChecklistBase.java
+++ b/src/main/java/com/project/dorumdorum/domain/checklist/domain/entity/ChecklistBase.java
@@ -123,6 +123,17 @@ public abstract class ChecklistBase {
     @Column(name = "updated_at", nullable = false)
     private LocalDateTime updatedAt;
 
+    @Column(name = "deleted_at")
+    private LocalDateTime deletedAt;
+
+    public boolean isDeleted() {
+        return deletedAt != null;
+    }
+
+    public void delete() {
+        deletedAt = LocalDateTime.now();
+    }
+
     public void updateChecklist(
             String bedtime,
             String wakeUp,
diff --git a/src/main/java/com/project/dorumdorum/domain/checklist/domain/entity/RoomRule.java b/src/main/java/com/project/dorumdorum/domain/checklist/domain/entity/RoomRule.java
index c14534a2..2f989717 100644
--- a/src/main/java/com/project/dorumdorum/domain/checklist/domain/entity/RoomRule.java
+++ b/src/main/java/com/project/dorumdorum/domain/checklist/domain/entity/RoomRule.java
@@ -6,8 +6,10 @@
 import lombok.Getter;
 import lombok.NoArgsConstructor;
 import lombok.experimental.SuperBuilder;
+import org.hibernate.annotations.SQLRestriction;
 
 @Entity
+@SQLRestriction("deleted_at is null")
 @Table(
         name = "room_rule",
         indexes = {
diff --git a/src/main/java/com/project/dorumdorum/domain/checklist/domain/repository/RoomRuleRepository.java b/src/main/java/com/project/dorumdorum/domain/checklist/domain/repository/RoomRuleRepository.java
index 4a09be02..4b7eeab3 100644
--- a/src/main/java/com/project/dorumdorum/domain/checklist/domain/repository/RoomRuleRepository.java
+++ b/src/main/java/com/project/dorumdorum/domain/checklist/domain/repository/RoomRuleRepository.java
@@ -14,6 +14,6 @@ public interface RoomRuleRepository extends JpaRepository<RoomRule, String> {
     Optional<RoomRule> findByRoomNo(@Param("roomNo") String roomNo);
 
     @Modifying(clearAutomatically = true, flushAutomatically = true)
-    @Query("DELETE FROM RoomRule rr WHERE rr.room.roomNo = :roomNo")
+    @Query("UPDATE RoomRule rr SET rr.deletedAt = CURRENT_TIMESTAMP WHERE rr.room.roomNo = :roomNo AND rr.deletedAt IS NULL")
     void deleteByRoomNo(@Param("roomNo") String roomNo);
 }
diff --git a/src/main/java/com/project/dorumdorum/domain/room/application/usecase/DeleteRoomUseCase.java b/src/main/java/com/project/dorumdorum/domain/room/application/usecase/DeleteRoomUseCase.java
index e77cae89..65fe1cad 100644
--- a/src/main/java/com/project/dorumdorum/domain/room/application/usecase/DeleteRoomUseCase.java
+++ b/src/main/java/com/project/dorumdorum/domain/room/application/usecase/DeleteRoomUseCase.java
@@ -33,8 +33,8 @@ public class DeleteRoomUseCase {
      * 방 삭제
      * - 방장 권한 검증
      * - 방장 외 룸메이트 존재 시 삭제 불가
-     * - 방 소프트 삭제 → 룸메이트 퇴실 처리 → flush(deletedAt DB 반영)
-     * - RoomRequest, RoomRule, RoomLike 연관 데이터 삭제
+     * - 방 소프트 삭제 → 룸메이트 퇴실 처리
+     * - RoomRequest, RoomRule, RoomLike 연관 데이터 삭제 (@Modifying flushAutomatically로 자동 flush)
      * - 채팅방 삭제 이벤트 발행
      */
     public void execute(String requesterNo, String roomNo) {
@@ -54,7 +54,6 @@ public void execute(String requesterNo, String roomNo) {
 
         room.delete();
         roommateService.leaveRoom(requesterNo, roomNo);
-        roomService.flush();
 
         roomRequestService.deleteAllByRoom(room);
         roomRuleService.deleteByRoomNo(roomNo);
diff --git a/src/main/java/com/project/dorumdorum/domain/room/application/usecase/KickRoommateUseCase.java b/src/main/java/com/project/dorumdorum/domain/room/application/usecase/KickRoommateUseCase.java
index c56b398e..70bab830 100644
--- a/src/main/java/com/project/dorumdorum/domain/room/application/usecase/KickRoommateUseCase.java
+++ b/src/main/java/com/project/dorumdorum/domain/room/application/usecase/KickRoommateUseCase.java
@@ -41,7 +41,6 @@ public void execute(String requesterNo, String roomNo, String kickedUserNo) {
 
         roommateService.leaveRoom(kickedUserNo, roomNo);
         room.minusCurrentMate();
-        roomService.flush();
 
         eventPublisher.publishEvent(new RoommateKickedEvent(roomNo, kickedUserNo));
     }
diff --git a/src/main/java/com/project/dorumdorum/domain/room/domain/entity/RoomLike.java b/src/main/java/com/project/dorumdorum/domain/room/domain/entity/RoomLike.java
index bb492fbb..0b4437a1 100644
--- a/src/main/java/com/project/dorumdorum/domain/room/domain/entity/RoomLike.java
+++ b/src/main/java/com/project/dorumdorum/domain/room/domain/entity/RoomLike.java
@@ -4,16 +4,15 @@
 import io.hypersistence.utils.hibernate.id.Tsid;
 import jakarta.persistence.*;
 import lombok.*;
+import org.hibernate.annotations.SQLRestriction;
 
 @Entity
 @Getter
 @NoArgsConstructor(access = AccessLevel.PROTECTED)
 @AllArgsConstructor(access = AccessLevel.PROTECTED)
 @Builder
+@SQLRestriction("deleted_at is null")
 @Table(
-        uniqueConstraints = {
-                @UniqueConstraint(name = "uk_room_like_user_room", columnNames = {"user_no", "room_no"})
-        },
         indexes = {
         }
 )
diff --git a/src/main/java/com/project/dorumdorum/domain/room/domain/entity/RoomRequest.java b/src/main/java/com/project/dorumdorum/domain/room/domain/entity/RoomRequest.java
index 0f2745c3..0ae886d7 100644
--- a/src/main/java/com/project/dorumdorum/domain/room/domain/entity/RoomRequest.java
+++ b/src/main/java/com/project/dorumdorum/domain/room/domain/entity/RoomRequest.java
@@ -4,16 +4,15 @@
 import io.hypersistence.utils.hibernate.id.Tsid;
 import jakarta.persistence.*;
 import lombok.*;
+import org.hibernate.annotations.SQLRestriction;
 
 @Entity
 @Getter
 @NoArgsConstructor(access = AccessLevel.PROTECTED)
 @AllArgsConstructor(access = AccessLevel.PROTECTED)
 @Builder
+@SQLRestriction("deleted_at is null")
 @Table(
-        uniqueConstraints = {
-                @UniqueConstraint(name = "uk_room_request_user_room_direction", columnNames = {"user_no", "room_no", "direction"})
-        },
         indexes = {
                 @Index(name = "idx_room_request_room_created", columnList = "room_no, created_at")
         }
diff --git a/src/main/java/com/project/dorumdorum/domain/room/domain/repository/RoomLikeRepository.java b/src/main/java/com/project/dorumdorum/domain/room/domain/repository/RoomLikeRepository.java
index 93dc5350..3cbc3e75 100644
--- a/src/main/java/com/project/dorumdorum/domain/room/domain/repository/RoomLikeRepository.java
+++ b/src/main/java/com/project/dorumdorum/domain/room/domain/repository/RoomLikeRepository.java
@@ -10,11 +10,13 @@
 public interface RoomLikeRepository extends JpaRepository<RoomLike, String> {
 
     boolean existsByUserNoAndRoom(String userNo, Room room);
-    void deleteByUserNoAndRoom(String userNo, Room room);
 
-    // N+1 DELETE 문제 — @Modifying JPQL 벌크 DELETE로 교체
     @Modifying(clearAutomatically = true, flushAutomatically = true)
-    @Query("DELETE FROM RoomLike l WHERE l.room = :room")
+    @Query("UPDATE RoomLike l SET l.deletedAt = CURRENT_TIMESTAMP WHERE l.userNo = :userNo AND l.room = :room AND l.deletedAt IS NULL")
+    void deleteByUserNoAndRoom(@Param("userNo") String userNo, @Param("room") Room room);
+
+    @Modifying(clearAutomatically = true, flushAutomatically = true)
+    @Query("UPDATE RoomLike l SET l.deletedAt = CURRENT_TIMESTAMP WHERE l.room = :room AND l.deletedAt IS NULL")
     void deleteAllByRoom(@Param("room") Room room);
 }
 
diff --git a/src/main/java/com/project/dorumdorum/domain/room/domain/repository/RoomRequestRepository.java b/src/main/java/com/project/dorumdorum/domain/room/domain/repository/RoomRequestRepository.java
index 137d8315..8c28d784 100644
--- a/src/main/java/com/project/dorumdorum/domain/room/domain/repository/RoomRequestRepository.java
+++ b/src/main/java/com/project/dorumdorum/domain/room/domain/repository/RoomRequestRepository.java
@@ -15,9 +15,8 @@ public interface RoomRequestRepository extends JpaRepository<RoomRequest, String
     boolean existsByUserNoAndRoom(String userNo, Room room);
     Optional<RoomRequest> findByUserNoAndRoomAndDirection(String userNo, Room room, Direction direction);
 
-    // N+1 DELETE 문제 — @Modifying JPQL 벌크 DELETE로 교체
     @Modifying(clearAutomatically = true, flushAutomatically = true)
-    @Query("DELETE FROM RoomRequest r WHERE r.room = :room")
+    @Query("UPDATE RoomRequest r SET r.deletedAt = CURRENT_TIMESTAMP WHERE r.room = :room AND r.deletedAt IS NULL")
     void deleteAllByRoom(@Param("room") Room room);
 }
 
diff --git a/src/main/java/com/project/dorumdorum/domain/room/domain/service/RoomRequestService.java b/src/main/java/com/project/dorumdorum/domain/room/domain/service/RoomRequestService.java
index fcf0532d..42b05efb 100644
--- a/src/main/java/com/project/dorumdorum/domain/room/domain/service/RoomRequestService.java
+++ b/src/main/java/com/project/dorumdorum/domain/room/domain/service/RoomRequestService.java
@@ -42,7 +42,8 @@ public RoomRequest findById(String requestNo) {
     }
 
     public void delete(RoomRequest entity) {
-        roomRequestRepository.delete(entity);
+        entity.delete();
+        roomRequestRepository.save(entity);
     }
 
     public List<RoomRequestApplicationResponse> findApplicationsByRoom(Room room) {
@@ -54,7 +55,8 @@ public void cancelJoinRequest(String userNo, Room room) {
                 .findByUserNoAndRoomAndDirection(userNo, room, Direction.USER_TO_ROOM)
                 .orElseThrow(() -> new RestApiException(ROOM_REQUEST_NOT_FOUND));
 
-        roomRequestRepository.delete(request);
+        request.delete();
+        roomRequestRepository.save(request);
     }
 
     public void deleteAllByRoom(Room room) {
diff --git a/src/main/java/com/project/dorumdorum/domain/room/domain/service/RoomService.java b/src/main/java/com/project/dorumdorum/domain/room/domain/service/RoomService.java
index e2877e2e..da9c00cd 100644
--- a/src/main/java/com/project/dorumdorum/domain/room/domain/service/RoomService.java
+++ b/src/main/java/com/project/dorumdorum/domain/room/domain/service/RoomService.java
@@ -61,10 +61,6 @@ public FindRoomsResponse findMyRoom(String userNo) {
                 .orElseThrow(() -> new RestApiException(ROOM_NOT_FOUND));
     }
 
-    public void flush() {
-        roomRepository.flush();
-    }
-
     public List<FindRoomsResponse> findLikedRooms(String userNo) {
         return roomRepository.findLikedRooms(userNo);
     }
diff --git a/src/main/java/com/project/dorumdorum/domain/roommate/domain/entity/Roommate.java b/src/main/java/com/project/dorumdorum/domain/roommate/domain/entity/Roommate.java
index 2f5c485f..e00ff019 100644
--- a/src/main/java/com/project/dorumdorum/domain/roommate/domain/entity/Roommate.java
+++ b/src/main/java/com/project/dorumdorum/domain/roommate/domain/entity/Roommate.java
@@ -5,16 +5,15 @@
 import io.hypersistence.utils.hibernate.id.Tsid;
 import jakarta.persistence.*;
 import lombok.*;
+import org.hibernate.annotations.SQLRestriction;
 
 @Entity
 @Getter
 @NoArgsConstructor(access = AccessLevel.PROTECTED)
 @AllArgsConstructor(access = AccessLevel.PROTECTED)
 @Builder
+@SQLRestriction("deleted_at is null")
 @Table(
-        uniqueConstraints = {
-                @UniqueConstraint(name = "uk_roommate_user_no", columnNames = "user_no")
-        },
         indexes = {
                 @Index(name = "idx_roommate_room_no", columnList = "room_no")
         }
diff --git a/src/main/java/com/project/dorumdorum/domain/roommate/domain/service/RoommateService.java b/src/main/java/com/project/dorumdorum/domain/roommate/domain/service/RoommateService.java
index b503f1da..54c135ca 100644
--- a/src/main/java/com/project/dorumdorum/domain/roommate/domain/service/RoommateService.java
+++ b/src/main/java/com/project/dorumdorum/domain/roommate/domain/service/RoommateService.java
@@ -66,8 +66,8 @@ public boolean isHostOfRoom(String userNo, String roomNo) {
     public void leaveRoom(String userNo, String roomNo) {
         Roommate roommate = roommateRepository.findByUserNoAndRoomNo(userNo, roomNo)
                 .orElseThrow(() -> new RestApiException(_NOT_FOUND));
-        // uk_roommate_user_no 유니크 제약으로 인해 소프트 삭제 불가 — 하드 삭제 유지
-        roommateRepository.delete(roommate);
+        roommate.delete();
+        roommateRepository.save(roommate);
     }
 
     public List<MyRoommateResponse> findMyRoommates(String userNo) {
diff --git a/src/main/resources/application-prod.yml b/src/main/resources/application-prod.yml
index 94c25035..f204d39b 100644
--- a/src/main/resources/application-prod.yml
+++ b/src/main/resources/application-prod.yml
@@ -1,13 +1,17 @@
 server:
   shutdown: graceful
+  tomcat:
+    threads:
+      max: 100
+      min-spare: 10
 
 spring:
   lifecycle:
     timeout-per-shutdown-phase: 30s
   datasource:
     hikari:
-      maximum-pool-size: 16
-      minimum-idle: 4
+      maximum-pool-size: 8
+      minimum-idle: 2
       connection-timeout: 5000
       validation-timeout: 1000
       idle-timeout: 600000
diff --git a/src/main/resources/schema.sql b/src/main/resources/schema.sql
index 8f90ec5b..bd343ded 100644
--- a/src/main/resources/schema.sql
+++ b/src/main/resources/schema.sql
@@ -4,17 +4,34 @@ CREATE UNIQUE INDEX IF NOT EXISTS uk_user_email
 CREATE UNIQUE INDEX IF NOT EXISTS uk_user_student_no
     ON users (student_no);
 
+ALTER TABLE IF EXISTS room_rule ADD COLUMN IF NOT EXISTS deleted_at TIMESTAMP;
+
+ALTER TABLE IF EXISTS roommate DROP CONSTRAINT IF EXISTS uk_roommate_user_no;
+DROP INDEX IF EXISTS uk_roommate_user_no;
 CREATE UNIQUE INDEX IF NOT EXISTS uk_roommate_user_no
-    ON roommate (user_no);
+    ON roommate (user_no)
+    WHERE deleted_at IS NULL;
 
+ALTER TABLE IF EXISTS room_like DROP CONSTRAINT IF EXISTS uk_room_like_user_room;
+DROP INDEX IF EXISTS uk_room_like_user_room;
 CREATE UNIQUE INDEX IF NOT EXISTS uk_room_like_user_room
-    ON room_like (user_no, room_no);
+    ON room_like (user_no, room_no)
+    WHERE deleted_at IS NULL;
 
 CREATE UNIQUE INDEX IF NOT EXISTS uk_device_user_device
     ON devices (user_no, device_id);
 
+ALTER TABLE IF EXISTS room_request DROP CONSTRAINT IF EXISTS uk_room_request_user_room_direction;
+DROP INDEX IF EXISTS uk_room_request_user_room_direction;
 CREATE UNIQUE INDEX IF NOT EXISTS uk_room_request_user_room_direction
-    ON room_request (user_no, room_no, direction);
+    ON room_request (user_no, room_no, direction)
+    WHERE deleted_at IS NULL;
+
+ALTER TABLE IF EXISTS chat_room_member DROP CONSTRAINT IF EXISTS uk_chat_room_member_room_user;
+DROP INDEX IF EXISTS uk_chat_room_member_room_user;
+CREATE UNIQUE INDEX IF NOT EXISTS uk_chat_room_member_room_user
+    ON chat_room_member (chat_room_no, user_no)
+    WHERE deleted_at IS NULL;
 
 ALTER TABLE IF EXISTS users
     ALTER COLUMN gender SET NOT NULL;
@@ -30,13 +47,15 @@ CREATE INDEX IF NOT EXISTS idx_room_status_gender_remaining_created
 ALTER TABLE IF EXISTS chat_room
     DROP CONSTRAINT IF EXISTS uk_chat_room_direct;
 
+DROP INDEX IF EXISTS uk_chat_room_group;
 CREATE UNIQUE INDEX IF NOT EXISTS uk_chat_room_group
     ON chat_room (room_no)
-    WHERE chat_room_type = 'GROUP';
+    WHERE chat_room_type = 'GROUP' AND deleted_at IS NULL;
 
+DROP INDEX IF EXISTS uk_chat_room_direct;
 CREATE UNIQUE INDEX IF NOT EXISTS uk_chat_room_direct
     ON chat_room (room_no, applicant_user_no)
-    WHERE chat_room_type = 'DIRECT';
+    WHERE chat_room_type = 'DIRECT' AND deleted_at IS NULL;
 
 CREATE INDEX IF NOT EXISTS idx_chat_room_room_no
     ON chat_room (room_no);
diff --git a/src/test/java/com/project/dorumdorum/domain/chat/integration/ChatTransactionAtomicityIntegrationTest.java b/src/test/java/com/project/dorumdorum/domain/chat/integration/ChatTransactionAtomicityIntegrationTest.java
index eb13a2f7..f59c82d3 100644
--- a/src/test/java/com/project/dorumdorum/domain/chat/integration/ChatTransactionAtomicityIntegrationTest.java
+++ b/src/test/java/com/project/dorumdorum/domain/chat/integration/ChatTransactionAtomicityIntegrationTest.java
@@ -33,6 +33,7 @@
 import org.springframework.messaging.simp.SimpMessagingTemplate;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.jdbc.core.JdbcTemplate;
 import org.springframework.test.context.bean.override.mockito.MockitoBean;
 import org.springframework.test.context.bean.override.mockito.MockitoSpyBean;
 import org.springframework.test.context.ActiveProfiles;
@@ -88,6 +89,7 @@ static void requireDocker() {
     @Autowired private RoommateRepository roommateRepository;
     @Autowired private ChatRoomRepository chatRoomRepository;
     @Autowired private ChatRoomMemberRepository chatRoomMemberRepository;
+    @Autowired private JdbcTemplate jdbcTemplate;
 
     // ─── External Services (Mocking to isolate behavior) ─────────────────────
     @MockitoBean private SimpMessagingTemplate messagingTemplate;
@@ -110,6 +112,8 @@ static void requireDocker() {
 
     @BeforeEach
     void setUp() {
+        truncateTables();
+
         // 1. Room 저장 (@PrePersist → currentMateCount=1, roomStatus=CONFIRM_PENDING 자동 설정)
         room = roomRepository.save(
                 Room.builder()
@@ -162,11 +166,7 @@ void setUp() {
 
     @AfterEach
     void tearDown() {
-        // FK 순서: ChatRoomMember → ChatRoom → Roommate → Room
-        chatRoomMemberRepository.deleteAll();
-        chatRoomRepository.deleteAll();
-        roommateRepository.deleteAll();
-        roomRepository.deleteAll();
+        truncateTables();
     }
 
     // =========================================================================
@@ -345,4 +345,19 @@ private void stubChatMessageService() {
                 .when(chatMessageService)
                 .save(any(), anyString(), anyString(), any(), anyInt());
     }
+
+    private void truncateTables() {
+        jdbcTemplate.execute("""
+                TRUNCATE TABLE
+                    chat_message,
+                    chat_room_member,
+                    chat_room,
+                    room_request,
+                    room_rule,
+                    room_like,
+                    roommate,
+                    room
+                RESTART IDENTITY CASCADE
+                """);
+    }
 }
diff --git a/src/test/java/com/project/dorumdorum/domain/chat/unit/service/ChatRoomMemberServiceTest.java b/src/test/java/com/project/dorumdorum/domain/chat/unit/service/ChatRoomMemberServiceTest.java
index b3ad6add..5d62930b 100644
--- a/src/test/java/com/project/dorumdorum/domain/chat/unit/service/ChatRoomMemberServiceTest.java
+++ b/src/test/java/com/project/dorumdorum/domain/chat/unit/service/ChatRoomMemberServiceTest.java
@@ -121,13 +121,14 @@ void countByChatRoom_DelegatesToRepository() {
     }
 
     @Test
-    @DisplayName("leave: repository.delete에 위임")
-    void leave_DelegatesToRepository() {
+    @DisplayName("leave: 멤버를 소프트 삭제하고 저장")
+    void leave_SoftDeletesAndSaves() {
         ChatRoomMember member = ChatRoomMember.builder().chatRoom(chatRoom).userNo("user-1").build();
 
         service.leave(member);
 
-        verify(chatRoomMemberRepository).delete(member);
+        assertThat(member.getDeletedAt()).isNotNull();
+        verify(chatRoomMemberRepository).save(member);
     }
 
     @Test
diff --git a/src/test/java/com/project/dorumdorum/domain/chat/unit/service/ChatRoomServiceTest.java b/src/test/java/com/project/dorumdorum/domain/chat/unit/service/ChatRoomServiceTest.java
index 757773fe..24461a39 100644
--- a/src/test/java/com/project/dorumdorum/domain/chat/unit/service/ChatRoomServiceTest.java
+++ b/src/test/java/com/project/dorumdorum/domain/chat/unit/service/ChatRoomServiceTest.java
@@ -95,13 +95,14 @@ void updateLastMessage_UpdatesFields() {
     }
 
     @Test
-    @DisplayName("delete: repository.delete에 위임")
-    void delete_DelegatesToRepository() {
+    @DisplayName("delete: 채팅방을 소프트 삭제하고 저장")
+    void delete_SoftDeletesAndSaves() {
         ChatRoom chatRoom = ChatRoom.builder().roomNo("room-1").build();
 
         service.delete(chatRoom);
 
-        verify(chatRoomRepository).delete(chatRoom);
+        assertThat(chatRoom.getDeletedAt()).isNotNull();
+        verify(chatRoomRepository).save(chatRoom);
     }
 
     @Test
diff --git a/src/test/java/com/project/dorumdorum/domain/room/integration/DeleteRoomPersistenceIntegrationTest.java b/src/test/java/com/project/dorumdorum/domain/room/integration/DeleteRoomPersistenceIntegrationTest.java
index 43d568a4..c5771712 100644
--- a/src/test/java/com/project/dorumdorum/domain/room/integration/DeleteRoomPersistenceIntegrationTest.java
+++ b/src/test/java/com/project/dorumdorum/domain/room/integration/DeleteRoomPersistenceIntegrationTest.java
@@ -34,6 +34,7 @@
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.jdbc.core.JdbcTemplate;
 import org.springframework.messaging.simp.SimpMessagingTemplate;
 import org.springframework.test.context.ActiveProfiles;
 import org.springframework.test.context.bean.override.mockito.MockitoBean;
@@ -74,6 +75,7 @@ static void requireDocker() {
     @Autowired private ChatRoomRepository chatRoomRepository;
     @Autowired private ChatRoomMemberRepository chatRoomMemberRepository;
     @Autowired private ChatMessageRepository chatMessageRepository;
+    @Autowired private JdbcTemplate jdbcTemplate;
 
     private static final String HOST_NO      = "test_delete_room_host_001";
     private static final String APPLICANT_NO = "test_delete_room_applicant_001";
@@ -82,6 +84,8 @@ static void requireDocker() {
 
     @BeforeEach
     void setUp() {
+        truncateTables();
+
         room = roomRepository.save(Room.builder()
                 .roomType(RoomType.TYPE_1)
                 .capacity(2)
@@ -165,13 +169,7 @@ void setUp() {
 
     @AfterEach
     void tearDown() {
-        chatMessageRepository.deleteAllInBatch();
-        chatRoomMemberRepository.deleteAllInBatch();
-        chatRoomRepository.deleteAllInBatch();
-        roomRequestRepository.deleteAllInBatch();
-        roomRuleRepository.deleteAllInBatch();
-        roommateRepository.deleteAllInBatch();
-        roomRepository.deleteAllInBatch();
+        truncateTables();
     }
 
     @Test
@@ -193,4 +191,19 @@ void execute_PersistsSoftDeleteAndCleanup() {
                 verify(messagingTemplate, times(3))
                         .convertAndSendToUser(any(), eq("/queue/notification"), any()));
     }
+
+    private void truncateTables() {
+        jdbcTemplate.execute("""
+                TRUNCATE TABLE
+                    chat_message,
+                    chat_room_member,
+                    chat_room,
+                    room_request,
+                    room_rule,
+                    room_like,
+                    roommate,
+                    room
+                RESTART IDENTITY CASCADE
+                """);
+    }
 }
diff --git a/src/test/java/com/project/dorumdorum/domain/room/integration/FlushRemovalIntegrationTest.java b/src/test/java/com/project/dorumdorum/domain/room/integration/FlushRemovalIntegrationTest.java
new file mode 100644
index 00000000..10fc2b66
--- /dev/null
+++ b/src/test/java/com/project/dorumdorum/domain/room/integration/FlushRemovalIntegrationTest.java
@@ -0,0 +1,228 @@
+package com.project.dorumdorum.domain.room.integration;
+
+import com.google.firebase.FirebaseApp;
+import com.google.firebase.messaging.FirebaseMessaging;
+import com.project.dorumdorum.domain.chat.domain.entity.ChatRoom;
+import com.project.dorumdorum.domain.chat.domain.entity.ChatRoomMember;
+import com.project.dorumdorum.domain.chat.domain.repository.ChatMessageRepository;
+import com.project.dorumdorum.domain.chat.domain.repository.ChatRoomMemberRepository;
+import com.project.dorumdorum.domain.chat.domain.repository.ChatRoomRepository;
+import com.project.dorumdorum.domain.chat.domain.service.ChatMessageService;
+import com.project.dorumdorum.domain.chat.domain.service.ChatRoomMemberService;
+import com.project.dorumdorum.domain.checklist.domain.repository.RoomRuleRepository;
+import com.project.dorumdorum.domain.room.application.usecase.DeleteRoomUseCase;
+import com.project.dorumdorum.domain.room.application.usecase.KickRoommateUseCase;
+import com.project.dorumdorum.domain.room.domain.entity.ResidencePeriod;
+import com.project.dorumdorum.domain.room.domain.entity.Room;
+import com.project.dorumdorum.domain.room.domain.entity.RoomType;
+import com.project.dorumdorum.domain.room.domain.repository.RoomLikeRepository;
+import com.project.dorumdorum.domain.room.domain.repository.RoomRepository;
+import com.project.dorumdorum.domain.room.domain.repository.RoomRequestRepository;
+import com.project.dorumdorum.domain.roommate.domain.entity.ConfirmStatus;
+import com.project.dorumdorum.domain.roommate.domain.entity.RoomRole;
+import com.project.dorumdorum.domain.roommate.domain.entity.Roommate;
+import com.project.dorumdorum.domain.roommate.domain.repository.RoommateRepository;
+import com.project.dorumdorum.domain.user.domain.entity.Gender;
+import com.project.dorumdorum.domain.user.domain.entity.Role;
+import com.project.dorumdorum.domain.user.domain.entity.User;
+import com.project.dorumdorum.domain.user.domain.service.UserService;
+import com.project.dorumdorum.testsupport.TestcontainersSupport;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.Assumptions;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.messaging.simp.SimpMessagingTemplate;
+import org.springframework.test.context.ActiveProfiles;
+import org.springframework.test.context.bean.override.mockito.MockitoBean;
+import org.springframework.test.context.bean.override.mockito.MockitoSpyBean;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyInt;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+/**
+ * 명시적 flush() 제거 후 실제 DB 반영 검증 통합 테스트.
+ *
+ * 검증 대상:
+ * 1. KickRoommateUseCase — room.minusCurrentMate()가 flushAutomatically(BEFORE_COMMIT 리스너
+ *    내 decreaseUnreadCount)를 통해 DB에 반영되는지
+ * 2. DeleteRoomUseCase — room.delete()가 deleteAllByRoom(flushAutomatically=true)를 통해
+ *    DB에 반영되고 연관 데이터가 정리되는지
+ *
+ * @ActiveProfiles("test"): Testcontainers PostgreSQL로 실제 DB 동작을 검증한다.
+ */
+@SpringBootTest
+@ActiveProfiles("test")
+@DisplayName("flush() 제거 후 실제 DB 반영 통합 테스트")
+class FlushRemovalIntegrationTest {
+
+    @BeforeAll
+    static void requireDocker() {
+        Assumptions.assumeTrue(
+                TestcontainersSupport.requireDockerOrSkip("FlushRemovalIntegrationTest"),
+                "Docker is required for FlushRemovalIntegrationTest"
+        );
+    }
+
+    @MockitoBean private FirebaseApp firebaseApp;
+    @MockitoBean private FirebaseMessaging firebaseMessaging;
+    @MockitoBean private SimpMessagingTemplate messagingTemplate;
+
+    @MockitoSpyBean private UserService userService;
+    @MockitoSpyBean private ChatMessageService chatMessageService;
+    @MockitoSpyBean private ChatRoomMemberService chatRoomMemberService;
+
+    @Autowired private KickRoommateUseCase kickRoommateUseCase;
+    @Autowired private DeleteRoomUseCase deleteRoomUseCase;
+
+    @Autowired private RoomRepository roomRepository;
+    @Autowired private RoommateRepository roommateRepository;
+    @Autowired private ChatRoomRepository chatRoomRepository;
+    @Autowired private ChatRoomMemberRepository chatRoomMemberRepository;
+    @Autowired private ChatMessageRepository chatMessageRepository;
+    @Autowired private RoomRequestRepository roomRequestRepository;
+    @Autowired private RoomRuleRepository roomRuleRepository;
+    @Autowired private RoomLikeRepository roomLikeRepository;
+    @Autowired private JdbcTemplate jdbcTemplate;
+
+    private static final String KICK_HOST_NO   = "flush_test_kick_host_001";
+    private static final String KICK_MEMBER_NO = "flush_test_kick_member_001";
+    private static final String DELETE_HOST_NO = "flush_test_del_host_001";
+
+    private Room kickRoom;
+    private ChatRoom kickChatRoom;
+    private Room deleteRoom;
+
+    @BeforeEach
+    void setUp() {
+        truncateTables();
+
+        // ── KickRoommateUseCase 픽스처 ────────────────────────────────────────
+        kickRoom = roomRepository.save(Room.builder()
+                .roomType(RoomType.TYPE_1).capacity(2).title("kick-flush-test")
+                .hostUserNo(KICK_HOST_NO).residencePeriod(ResidencePeriod.SEMESTER)
+                .gender(Gender.MALE).build());
+        kickRoom.plusCurrentMate();
+        kickRoom = roomRepository.saveAndFlush(kickRoom);
+
+        roommateRepository.save(Roommate.builder().room(kickRoom).userNo(KICK_HOST_NO)
+                .roomRole(RoomRole.HOST).confirmStatus(ConfirmStatus.ACCEPTED).build());
+        roommateRepository.save(Roommate.builder().room(kickRoom).userNo(KICK_MEMBER_NO)
+                .roomRole(RoomRole.MEMBER).confirmStatus(ConfirmStatus.ACCEPTED).build());
+
+        kickChatRoom = chatRoomRepository.save(ChatRoom.builder().roomNo(kickRoom.getRoomNo()).build());
+        chatRoomMemberRepository.save(ChatRoomMember.builder().chatRoom(kickChatRoom).userNo(KICK_HOST_NO).build());
+        chatRoomMemberRepository.save(ChatRoomMember.builder().chatRoom(kickChatRoom).userNo(KICK_MEMBER_NO).build());
+
+        // ── DeleteRoomUseCase 픽스처 ─────────────────────────────────────────
+        deleteRoom = roomRepository.save(Room.builder()
+                .roomType(RoomType.TYPE_1).capacity(2).title("delete-flush-test")
+                .hostUserNo(DELETE_HOST_NO).residencePeriod(ResidencePeriod.SEMESTER)
+                .gender(Gender.MALE).build());
+
+        roommateRepository.save(Roommate.builder().room(deleteRoom).userNo(DELETE_HOST_NO)
+                .roomRole(RoomRole.HOST).confirmStatus(ConfirmStatus.ACCEPTED).build());
+
+        stubUserService();
+        stubChatMessageService();
+    }
+
+    @AfterEach
+    void tearDown() {
+        truncateTables();
+    }
+
+    // =========================================================================
+    // KickRoommateUseCase: room.minusCurrentMate() flush 검증
+    // =========================================================================
+
+    @Test
+    @DisplayName("강퇴 후 room.currentMateCount 감소가 DB에 반영된다 (explicit flush 없이)")
+    void kick_CurrentMateCountDecrement_PersistedWithoutExplicitFlush() {
+        int beforeCount = roomRepository.findById(kickRoom.getRoomNo()).orElseThrow().getCurrentMateCount();
+
+        kickRoommateUseCase.execute(KICK_HOST_NO, kickRoom.getRoomNo(), KICK_MEMBER_NO);
+
+        Room persisted = roomRepository.findById(kickRoom.getRoomNo()).orElseThrow();
+        assertThat(persisted.getCurrentMateCount())
+                .as("minusCurrentMate()가 flush 없이도 DB에 반영되어야 한다")
+                .isEqualTo(beforeCount - 1);
+    }
+
+    @Test
+    @DisplayName("강퇴 후 Roommate 삭제가 DB에 반영된다 (explicit flush 없이)")
+    void kick_RoommateDelete_PersistedWithoutExplicitFlush() {
+        kickRoommateUseCase.execute(KICK_HOST_NO, kickRoom.getRoomNo(), KICK_MEMBER_NO);
+
+        assertThat(roommateRepository.existsByUserNoAndRoomNo(KICK_MEMBER_NO, kickRoom.getRoomNo()))
+                .as("Roommate 삭제가 DB에 반영되어야 한다")
+                .isFalse();
+    }
+
+    // =========================================================================
+    // DeleteRoomUseCase: room.delete() (deletedAt) flush 검증
+    // =========================================================================
+
+    @Test
+    @DisplayName("방 삭제 후 room.deletedAt이 DB에 반영된다 (explicit flush 없이)")
+    void delete_SoftDeletedAt_PersistedWithoutExplicitFlush() {
+        deleteRoomUseCase.execute(DELETE_HOST_NO, deleteRoom.getRoomNo());
+
+        Room persisted = roomRepository.findById(deleteRoom.getRoomNo()).orElseThrow();
+        assertThat(persisted.getDeletedAt())
+                .as("room.delete()가 flush 없이도 deletedAt이 DB에 반영되어야 한다")
+                .isNotNull();
+    }
+
+    @Test
+    @DisplayName("방 삭제 후 Roommate가 DB에서 제거된다 (explicit flush 없이)")
+    void delete_RoommateCleanup_PersistedWithoutExplicitFlush() {
+        deleteRoomUseCase.execute(DELETE_HOST_NO, deleteRoom.getRoomNo());
+
+        assertThat(roommateRepository.findByUserNo(DELETE_HOST_NO))
+                .as("방 삭제 시 Roommate가 DB에서 제거되어야 한다")
+                .isEmpty();
+    }
+
+    // =========================================================================
+    // 헬퍼
+    // =========================================================================
+
+    private void stubUserService() {
+        User fakeUser = User.builder()
+                .nickname("테스트멤버").name("홍길동").email("flush-test@test.com")
+                .password("pw").role(Role.USER).studentNo("202499999").build();
+        doReturn(fakeUser).when(userService).findById(KICK_MEMBER_NO);
+    }
+
+    private void stubChatMessageService() {
+        var fakeMessage = mock(com.project.dorumdorum.domain.chat.domain.entity.ChatMessage.class);
+        when(fakeMessage.getMessageNo()).thenReturn("fake-flush-msg-001");
+        when(fakeMessage.getCreatedAt()).thenReturn(java.time.LocalDateTime.now());
+        doReturn(fakeMessage).when(chatMessageService).save(any(), anyString(), anyString(), any(), anyInt());
+    }
+
+    private void truncateTables() {
+        jdbcTemplate.execute("""
+                TRUNCATE TABLE
+                    chat_message,
+                    chat_room_member,
+                    chat_room,
+                    room_request,
+                    room_rule,
+                    room_like,
+                    roommate,
+                    room
+                RESTART IDENTITY CASCADE
+                """);
+    }
+}
diff --git a/src/test/java/com/project/dorumdorum/domain/room/integration/KickRoommatePersistenceIntegrationTest.java b/src/test/java/com/project/dorumdorum/domain/room/integration/KickRoommatePersistenceIntegrationTest.java
index 4f3451b7..6ee5557c 100644
--- a/src/test/java/com/project/dorumdorum/domain/room/integration/KickRoommatePersistenceIntegrationTest.java
+++ b/src/test/java/com/project/dorumdorum/domain/room/integration/KickRoommatePersistenceIntegrationTest.java
@@ -31,6 +31,7 @@
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.jdbc.core.JdbcTemplate;
 import org.springframework.messaging.simp.SimpMessagingTemplate;
 import org.springframework.test.context.ActiveProfiles;
 import org.springframework.test.context.bean.override.mockito.MockitoBean;
@@ -75,6 +76,7 @@ static void requireDocker() {
     @Autowired private ChatRoomRepository chatRoomRepository;
     @Autowired private ChatRoomMemberRepository chatRoomMemberRepository;
     @Autowired private ChatMessageRepository chatMessageRepository;
+    @Autowired private JdbcTemplate jdbcTemplate;
 
     private static final String HOST_NO   = "test_kick_roommate_host_001";
     private static final String MEMBER_NO = "test_kick_roommate_member_001";
@@ -84,6 +86,8 @@ static void requireDocker() {
 
     @BeforeEach
     void setUp() {
+        truncateTables();
+
         User fakeUser = User.builder()
                 .nickname("MemberNick")
                 .name("Member")
@@ -147,11 +151,7 @@ void setUp() {
 
     @AfterEach
     void tearDown() {
-        chatMessageRepository.deleteAllInBatch();
-        chatRoomMemberRepository.deleteAllInBatch();
-        chatRoomRepository.deleteAllInBatch();
-        roommateRepository.deleteAllInBatch();
-        roomRepository.deleteAllInBatch();
+        truncateTables();
     }
 
     @Test
@@ -172,4 +172,19 @@ void execute_PersistsKickChangesAcrossRoomAndChat() {
             verify(messagingTemplate).convertAndSendToUser(eq(MEMBER_NO), eq("/queue/notification"), any());
         });
     }
+
+    private void truncateTables() {
+        jdbcTemplate.execute("""
+                TRUNCATE TABLE
+                    chat_message,
+                    chat_room_member,
+                    chat_room,
+                    room_request,
+                    room_rule,
+                    room_like,
+                    roommate,
+                    room
+                RESTART IDENTITY CASCADE
+                """);
+    }
 }
diff --git a/src/test/java/com/project/dorumdorum/domain/room/unit/service/RoomRequestServiceTest.java b/src/test/java/com/project/dorumdorum/domain/room/unit/service/RoomRequestServiceTest.java
index 9db86ae8..1dedba72 100644
--- a/src/test/java/com/project/dorumdorum/domain/room/unit/service/RoomRequestServiceTest.java
+++ b/src/test/java/com/project/dorumdorum/domain/room/unit/service/RoomRequestServiceTest.java
@@ -62,11 +62,12 @@ void findById_WhenMissing_Throws() {
     }
 
     @Test
-    @DisplayName("Should delete provided request entity")
-    void delete_DeletesEntity() {
+    @DisplayName("Should soft delete provided request entity")
+    void delete_SoftDeletesEntity() {
         RoomRequest request = RoomRequest.builder().roomRequestNo("rq1").build();
         service.delete(request);
-        verify(roomRequestRepository).delete(request);
+        assertThat(request.getDeletedAt()).isNotNull();
+        verify(roomRequestRepository).save(request);
     }
 
     @Test
@@ -87,8 +88,8 @@ void findApplicationsByRoom_ReturnsRepositoryResult() {
     }
 
     @Test
-    @DisplayName("Should cancel join request by user and room")
-    void cancelJoinRequest_FindsAndDeletesRequest() {
+    @DisplayName("Should cancel join request by soft deleting request")
+    void cancelJoinRequest_FindsAndSoftDeletesRequest() {
         Room room = Room.builder().roomNo("r1").build();
         RoomRequest request = RoomRequest.builder().roomRequestNo("rq1").build();
         when(roomRequestRepository.findByUserNoAndRoomAndDirection("u1", room, Direction.USER_TO_ROOM))
@@ -96,7 +97,8 @@ void cancelJoinRequest_FindsAndDeletesRequest() {
 
         service.cancelJoinRequest("u1", room);
 
-        verify(roomRequestRepository).delete(request);
+        assertThat(request.getDeletedAt()).isNotNull();
+        verify(roomRequestRepository).save(request);
     }
 
     @Test
diff --git a/src/test/java/com/project/dorumdorum/domain/room/unit/usecase/DeleteRoomUseCaseTest.java b/src/test/java/com/project/dorumdorum/domain/room/unit/usecase/DeleteRoomUseCaseTest.java
index 30cdcefa..ec74f967 100644
--- a/src/test/java/com/project/dorumdorum/domain/room/unit/usecase/DeleteRoomUseCaseTest.java
+++ b/src/test/java/com/project/dorumdorum/domain/room/unit/usecase/DeleteRoomUseCaseTest.java
@@ -97,7 +97,6 @@ void execute_WhenHostAlone_DeletesAndPublishesEvent() {
 
         verify(room).delete();
         verify(roommateService).leaveRoom("host", "r1");
-        verify(roomService).flush();
         verify(roomRequestService).deleteAllByRoom(room);
         verify(roomRuleService).deleteByRoomNo("r1");
         verify(roomLikeRepository).deleteAllByRoom(room);
@@ -105,7 +104,7 @@ void execute_WhenHostAlone_DeletesAndPublishesEvent() {
     }
 
     @Test
-    @DisplayName("cascade 삭제는 방 소프트 삭제 → 룸메이트 제거 → flush → 요청/규칙/좋아요 삭제 순서로 수행")
+    @DisplayName("cascade 삭제는 방 소프트 삭제 → 룸메이트 제거 → 요청/규칙/좋아요 삭제 순서로 수행")
     void execute_CascadeDeletesInOrder() {
         Room room = mock(Room.class);
         when(roomService.findByIdForUpdate("r1")).thenReturn(room);
@@ -115,10 +114,9 @@ void execute_CascadeDeletesInOrder() {
 
         useCase.execute("host", "r1");
 
-        InOrder inOrder = inOrder(room, roommateService, roomService, roomRequestService, roomRuleService, roomLikeRepository, eventPublisher);
+        InOrder inOrder = inOrder(room, roommateService, roomRequestService, roomRuleService, roomLikeRepository, eventPublisher);
         inOrder.verify(room).delete();
         inOrder.verify(roommateService).leaveRoom("host", "r1");
-        inOrder.verify(roomService).flush();
         inOrder.verify(roomRequestService).deleteAllByRoom(room);
         inOrder.verify(roomRuleService).deleteByRoomNo("r1");
         inOrder.verify(roomLikeRepository).deleteAllByRoom(room);
diff --git a/src/test/java/com/project/dorumdorum/domain/room/unit/usecase/KickRoommateUseCaseTest.java b/src/test/java/com/project/dorumdorum/domain/room/unit/usecase/KickRoommateUseCaseTest.java
index 8069eed2..f4396221 100644
--- a/src/test/java/com/project/dorumdorum/domain/room/unit/usecase/KickRoommateUseCaseTest.java
+++ b/src/test/java/com/project/dorumdorum/domain/room/unit/usecase/KickRoommateUseCaseTest.java
@@ -41,7 +41,6 @@ void execute_WhenHostKicksOther_Success() {
 
         verify(roommateService).leaveRoom("member1", "r1");
         verify(room).minusCurrentMate();
-        verify(roomService).flush();
         verify(eventPublisher).publishEvent(new RoommateKickedEvent("r1", "member1"));
     }
 
@@ -71,7 +70,6 @@ void execute_WhenKickedUserNotInRoom_ThrowsException() {
                 .isInstanceOf(RestApiException.class);
 
         verify(room, never()).minusCurrentMate();
-        verify(roomService, never()).flush();
         verify(eventPublisher, never()).publishEvent(any());
     }
 
@@ -86,7 +84,6 @@ void execute_WhenNotHost_ThrowsNoPermission() {
                 .isInstanceOf(RestApiException.class);
 
         verify(roommateService, never()).leaveRoom(any(), any());
-        verify(roomService, never()).flush();
         verify(eventPublisher, never()).publishEvent(any());
     }
 
@@ -101,7 +98,6 @@ void execute_WhenKickSelf_ThrowsCannotKickSelf() {
                 .isInstanceOf(RestApiException.class);
 
         verify(roommateService, never()).leaveRoom(any(), any());
-        verify(roomService, never()).flush();
         verify(eventPublisher, never()).publishEvent(any());
     }
 }
diff --git a/src/test/java/com/project/dorumdorum/domain/roommate/unit/service/RoommateServiceTest.java b/src/test/java/com/project/dorumdorum/domain/roommate/unit/service/RoommateServiceTest.java
index 60d4d8e7..fd3d0b1c 100644
--- a/src/test/java/com/project/dorumdorum/domain/roommate/unit/service/RoommateServiceTest.java
+++ b/src/test/java/com/project/dorumdorum/domain/roommate/unit/service/RoommateServiceTest.java
@@ -19,6 +19,8 @@
 import java.util.List;
 import java.util.Optional;
 
+import org.mockito.ArgumentCaptor;
+
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
 import static org.mockito.ArgumentMatchers.any;
@@ -198,4 +200,31 @@ void isHostOfRoom_WhenNotFound_ReturnsFalse() {
 
         assertThat(result).isFalse();
     }
+
+    @Test
+    @DisplayName("leaveRoom: 룸메이트를 소프트 삭제하고 저장한다")
+    void leaveRoom_SoftDeletesRoommate() {
+        Roommate roommate = Roommate.builder()
+                .roommateNo("rm1")
+                .userNo("u1")
+                .confirmStatus(ConfirmStatus.ACCEPTED)
+                .roomRole(RoomRole.MEMBER)
+                .build();
+        when(roommateRepository.findByUserNoAndRoomNo("u1", "room1")).thenReturn(Optional.of(roommate));
+
+        roommateService.leaveRoom("u1", "room1");
+
+        ArgumentCaptor<Roommate> captor = ArgumentCaptor.forClass(Roommate.class);
+        verify(roommateRepository).save(captor.capture());
+        assertThat(captor.getValue().isDeleted()).isTrue();
+    }
+
+    @Test
+    @DisplayName("leaveRoom: 룸메이트를 찾지 못하면 예외를 던진다")
+    void leaveRoom_WhenNotFound_Throws() {
+        when(roommateRepository.findByUserNoAndRoomNo("u1", "room1")).thenReturn(Optional.empty());
+
+        assertThatThrownBy(() -> roommateService.leaveRoom("u1", "room1"))
+                .isInstanceOf(RestApiException.class);
+    }
 }