diff --git a/src/features/votes/components/RelativeEvaluationBadge.svelte b/src/features/votes/components/RelativeEvaluationBadge.svelte
index cefff7294..04e5683b6 100644
--- a/src/features/votes/components/RelativeEvaluationBadge.svelte
+++ b/src/features/votes/components/RelativeEvaluationBadge.svelte
@@ -6,6 +6,7 @@
     calcGradeDiff,
     getRelativeEvaluationLabel,
     getRelativeEvaluationTooltipText,
+    getRelativeEvaluationBadgeColorClass,
   } from '$features/votes/utils/relative_evaluation';
 
   interface Props {
@@ -24,8 +25,9 @@
 
   let { officialGrade, medianGrade, badgeId, showTooltip = true }: Props = $props();
 
-  const label = $derived(getRelativeEvaluationLabel(calcGradeDiff(officialGrade, medianGrade)));
-  const isHarder = $derived(label.startsWith('+'));
+  const diff = $derived(calcGradeDiff(officialGrade, medianGrade));
+  const label = $derived(getRelativeEvaluationLabel(diff));
+  const badgeColorClass = $derived(getRelativeEvaluationBadgeColorClass(diff));
 
   const tooltipText = $derived(getRelativeEvaluationTooltipText(label));
 </script>
@@ -33,10 +35,7 @@
 {#if label}
   <span
     id={badgeId}
-    class="absolute -top-2 -right-2 z-10 rounded-full px-1 py-px text-[0.65rem] font-bold leading-none shadow-sm
-      {isHarder
-      ? 'bg-orange-400 text-white dark:bg-orange-500 dark:text-white'
-      : 'bg-sky-400 text-white dark:bg-sky-500 dark:text-white'}"
+    class="absolute -top-2 -right-2 z-10 rounded-full px-1 py-px text-[0.65rem] font-bold leading-none shadow-sm {badgeColorClass}"
     aria-hidden={!showTooltip}
     role={showTooltip ? 'img' : undefined}
     aria-label={showTooltip ? tooltipText : undefined}
diff --git a/src/features/votes/components/VotableGrade.svelte b/src/features/votes/components/VotableGrade.svelte
index 95fdf0eb2..457e02995 100644
--- a/src/features/votes/components/VotableGrade.svelte
+++ b/src/features/votes/components/VotableGrade.svelte
@@ -20,6 +20,8 @@
   import {
     calcGradeDiff,
     getRelativeEvaluationLabel,
+    getRelativeEvaluationJapaneseLabel,
+    getRelativeEvaluationColorClass,
   } from '$features/votes/utils/relative_evaluation';
   import { SIGNUP_PAGE, LOGIN_PAGE, EDIT_PROFILE_PAGE } from '$lib/constants/navbar-links';
 
@@ -207,16 +209,25 @@
   <Dropdown
     triggeredBy={`#update-grade-dropdown-trigger-${componentId}`}
     simple
-    class="h-48 w-25 z-50 border border-gray-200 dark:border-gray-100 overflow-y-auto"
+    class="h-48 w-44 z-50 border border-gray-200 dark:border-gray-100 overflow-y-auto"
   >
     {#each nonPendingGrades as grade (grade)}
       <DropdownItem onclick={() => handleClick(grade)} class="rounded-md">
         <div
-          class="flex items-center justify-between w-full text-gray-700 dark:text-gray-300 hover:text-gray-900 dark:hover:text-white"
+          class="flex items-center w-full gap-2 text-gray-700 dark:text-gray-300 hover:text-gray-900 dark:hover:text-white"
         >
-          <span>{getTaskGradeLabel(grade)}</span>
+          <span class="flex-1">{getTaskGradeLabel(grade)}</span>
+          {#if taskResult.grade !== TaskGrade.PENDING}
+            {@const diff = calcGradeDiff(taskResult.grade, grade)}
+            {@const relLabel = getRelativeEvaluationJapaneseLabel(diff)}
+            {#if relLabel}
+              <span class="w-16 text-right text-xs {getRelativeEvaluationColorClass(diff)}">
+                {relLabel}
+              </span>
+            {/if}
+          {/if}
           {#if votedGrade === grade}
-            <Check class="w-4 h-4 text-primary-600 dark:text-gray-300" strokeWidth={3} />
+            <Check class="w-4 h-4 shrink-0 text-primary-600 dark:text-gray-300" strokeWidth={3} />
           {/if}
         </div>
       </DropdownItem>
diff --git a/src/features/votes/utils/relative_evaluation.test.ts b/src/features/votes/utils/relative_evaluation.test.ts
index 39aa29085..710bcf747 100644
--- a/src/features/votes/utils/relative_evaluation.test.ts
+++ b/src/features/votes/utils/relative_evaluation.test.ts
@@ -5,6 +5,9 @@ import {
   calcGradeDiff,
   getRelativeEvaluationLabel,
   getRelativeEvaluationTooltipText,
+  getRelativeEvaluationJapaneseLabel,
+  getRelativeEvaluationColorClass,
+  getRelativeEvaluationBadgeColorClass,
 } from './relative_evaluation';
 
 describe('calcGradeDiff', () => {
@@ -121,3 +124,75 @@ describe('getRelativeEvaluationTooltipText', () => {
     expect(getRelativeEvaluationTooltipText('--')).toBe('ユーザは「易しい」と評価');
   });
 });
+
+describe('getRelativeEvaluationJapaneseLabel', () => {
+  test('returns "" for diff <= -3 (out of expected range)', () => {
+    expect(getRelativeEvaluationJapaneseLabel(-3)).toBe('');
+    expect(getRelativeEvaluationJapaneseLabel(-16)).toBe('');
+  });
+
+  test('returns "易しい" for diff === -2', () => {
+    expect(getRelativeEvaluationJapaneseLabel(-2)).toBe('易しい');
+  });
+
+  test('returns "やや易しい" for diff === -1', () => {
+    expect(getRelativeEvaluationJapaneseLabel(-1)).toBe('やや易しい');
+  });
+
+  test('returns "ふつう" for diff === 0', () => {
+    expect(getRelativeEvaluationJapaneseLabel(0)).toBe('ふつう');
+  });
+
+  test('returns "やや難しい" for diff === 1', () => {
+    expect(getRelativeEvaluationJapaneseLabel(1)).toBe('やや難しい');
+  });
+
+  test('returns "難しい" for diff === 2', () => {
+    expect(getRelativeEvaluationJapaneseLabel(2)).toBe('難しい');
+  });
+
+  test('returns "" for diff >= 3 (out of expected range)', () => {
+    expect(getRelativeEvaluationJapaneseLabel(3)).toBe('');
+    expect(getRelativeEvaluationJapaneseLabel(16)).toBe('');
+  });
+});
+
+describe('getRelativeEvaluationColorClass', () => {
+  test('returns sky text classes for negative diff (easier)', () => {
+    expect(getRelativeEvaluationColorClass(-1)).toBe('text-sky-500 dark:text-sky-400');
+    expect(getRelativeEvaluationColorClass(-16)).toBe('text-sky-500 dark:text-sky-400');
+  });
+
+  test('returns gray text classes for diff === 0', () => {
+    expect(getRelativeEvaluationColorClass(0)).toBe('text-gray-400 dark:text-gray-500');
+  });
+
+  test('returns orange text classes for positive diff (harder)', () => {
+    expect(getRelativeEvaluationColorClass(1)).toBe('text-orange-400 dark:text-orange-300');
+    expect(getRelativeEvaluationColorClass(16)).toBe('text-orange-400 dark:text-orange-300');
+  });
+});
+
+describe('getRelativeEvaluationBadgeColorClass', () => {
+  test('returns sky bg classes for negative diff (easier)', () => {
+    expect(getRelativeEvaluationBadgeColorClass(-1)).toBe(
+      'bg-sky-400 text-white dark:bg-sky-500 dark:text-white',
+    );
+    expect(getRelativeEvaluationBadgeColorClass(-16)).toBe(
+      'bg-sky-400 text-white dark:bg-sky-500 dark:text-white',
+    );
+  });
+
+  test('returns empty string for diff === 0 (badge not shown)', () => {
+    expect(getRelativeEvaluationBadgeColorClass(0)).toBe('');
+  });
+
+  test('returns orange bg classes for positive diff (harder)', () => {
+    expect(getRelativeEvaluationBadgeColorClass(1)).toBe(
+      'bg-orange-400 text-white dark:bg-orange-500 dark:text-white',
+    );
+    expect(getRelativeEvaluationBadgeColorClass(16)).toBe(
+      'bg-orange-400 text-white dark:bg-orange-500 dark:text-white',
+    );
+  });
+});
diff --git a/src/features/votes/utils/relative_evaluation.ts b/src/features/votes/utils/relative_evaluation.ts
index 5fd56c729..116cb58bd 100644
--- a/src/features/votes/utils/relative_evaluation.ts
+++ b/src/features/votes/utils/relative_evaluation.ts
@@ -13,6 +13,36 @@ export function calcGradeDiff(officialGrade: TaskGrade, medianGrade: TaskGrade):
   return getGradeOrder(medianGrade) - getGradeOrder(officialGrade);
 }
 
+/**
+ * Converts a grade difference to a 5-level relative evaluation label.
+ *
+ * | diff   | label |
+ * | ------ | ----- |
+ * | ≤ −2   | `--`  |
+ * | −1     | `-`   |
+ * |  0     | `""`  |
+ * | +1     | `+`   |
+ * | ≥ +2   | `++`  |
+ *
+ * @param diff - The result of {@link calcGradeDiff}.
+ * @returns The display label string.
+ */
+export function getRelativeEvaluationLabel(diff: number): string {
+  if (diff <= -2) {
+    return '--';
+  }
+  if (diff === -1) {
+    return '-';
+  }
+  if (diff === 0) {
+    return '';
+  }
+  if (diff === 1) {
+    return '+';
+  }
+  return '++';
+}
+
 /**
  * Returns a Japanese tooltip string explaining the relative evaluation label.
  *
@@ -35,31 +65,68 @@ export function getRelativeEvaluationTooltipText(label: string): string {
 }
 
 /**
- * Converts a grade difference to a 5-level relative evaluation label.
+ * Maps a grade difference to a Japanese label for display in the vote dropdown.
+ * Returns an empty string when the diff falls outside the expected ±2 range.
  *
- * | diff   | label |
- * | ------ | ----- |
- * | ≤ −2   | `--`  |
- * | −1     | `-`   |
- * |  0     | `""`  |
- * | +1     | `+`   |
- * | ≥ +2   | `++`  |
+ * | diff | label        |
+ * | ---- | ------------ |
+ * | ≤ −3 | `''`         |
+ * | −2   | `易しい`     |
+ * | −1   | `やや易しい` |
+ * |  0   | `ふつう`     |
+ * | +1   | `やや難しい` |
+ * | +2   | `難しい`     |
+ * | ≥ +3 | `''`         |
  *
- * @param diff - The result of {@link calcGradeDiff}.
- * @returns The display label string.
+ * @param diff - A grade difference (e.g., from {@link calcGradeDiff}).
+ * @returns The Japanese label string, or `''` if out of expected range.
  */
-export function getRelativeEvaluationLabel(diff: number): string {
-  if (diff <= -2) {
-    return '--';
+export function getRelativeEvaluationJapaneseLabel(diff: number): string {
+  switch (diff) {
+    case -2:
+      return '易しい';
+    case -1:
+      return 'やや易しい';
+    case 0:
+      return 'ふつう';
+    case 1:
+      return 'やや難しい';
+    case 2:
+      return '難しい';
+    default:
+      return '';
   }
-  if (diff === -1) {
-    return '-';
+}
+
+/**
+ * Returns Tailwind text color classes for a diff value in the vote dropdown.
+ * Negative diff (easier) → sky, zero → gray, positive (harder) → orange.
+ *
+ * @param diff - The result of {@link calcGradeDiff}.
+ */
+export function getRelativeEvaluationColorClass(diff: number): string {
+  if (diff < 0) {
+    return 'text-sky-500 dark:text-sky-400';
   }
   if (diff === 0) {
-    return '';
+    return 'text-gray-400 dark:text-gray-500';
   }
-  if (diff === 1) {
-    return '+';
+  return 'text-orange-400 dark:text-orange-300';
+}
+
+/**
+ * Returns Tailwind background + text color classes for the relative evaluation badge.
+ * Negative diff (easier) → sky, positive (harder) → orange.
+ * Returns empty string for diff === 0 (badge is not shown).
+ *
+ * @param diff - The result of {@link calcGradeDiff}.
+ */
+export function getRelativeEvaluationBadgeColorClass(diff: number): string {
+  if (diff < 0) {
+    return 'bg-sky-400 text-white dark:bg-sky-500 dark:text-white';
   }
-  return '++';
+  if (diff > 0) {
+    return 'bg-orange-400 text-white dark:bg-orange-500 dark:text-white';
+  }
+  return '';
 }