diff --git a/Core/Sources/Core/Configs/BoolConfigItem.swift b/Core/Sources/Core/Configs/BoolConfigItem.swift
index 5f32629..3c0b7b2 100644
--- a/Core/Sources/Core/Configs/BoolConfigItem.swift
+++ b/Core/Sources/Core/Configs/BoolConfigItem.swift
@@ -56,6 +56,12 @@ extension Config {
         static let `default` = false
         public static let key: String = "dev.ensan.inputmethod.azooKeyMac.preference.typeHalfSpace"
     }
+    /// Optionキー押下時に直接全角英数を入力する設定
+    public struct OptionDirectFullWidthInput: BoolConfigItem {
+        public init() {}
+        static let `default` = false
+        public static let key: String = "dev.ensan.inputmethod.azooKeyMac.preference.optionDirectFullWidthInput"
+    }
     /// AI変換時にコンテキストを含めるかどうか
     public struct IncludeContextInAITransform: BoolConfigItem {
         public init() {}
diff --git a/Core/Sources/Core/InputUtils/OptionDirectInputResolver.swift b/Core/Sources/Core/InputUtils/OptionDirectInputResolver.swift
new file mode 100644
index 0000000..0041c20
--- /dev/null
+++ b/Core/Sources/Core/InputUtils/OptionDirectInputResolver.swift
@@ -0,0 +1,43 @@
+import Foundation
+
+public enum OptionDirectInputResolver {
+    public static func resolve(
+        characters: String?,
+        modifierFlags: KeyEventCore.ModifierFlag,
+        inputLanguage: InputLanguage,
+        inputState: InputState,
+        typeBackSlash: Bool
+    ) -> String? {
+        guard inputLanguage == .japanese, inputState == .none else {
+            return nil
+        }
+        guard modifierFlags == [.option] || modifierFlags == [.option, .shift] else {
+            return nil
+        }
+        guard let characters,
+              !characters.isEmpty,
+              isPrintable(characters)
+        else {
+            return nil
+        }
+        let normalized = normalize(characters, typeBackSlash: typeBackSlash)
+        return normalized.applyingTransform(.fullwidthToHalfwidth, reverse: true)
+    }
+
+    private static func isPrintable(_ text: String) -> Bool {
+        let printable: CharacterSet = [.alphanumerics, .symbols, .punctuationCharacters]
+            .reduce(into: CharacterSet()) {
+                $0.formUnion($1)
+            }
+        return CharacterSet(text.unicodeScalars).isSubset(of: printable)
+    }
+
+    private static func normalize(_ text: String, typeBackSlash: Bool) -> String {
+        switch text {
+        case "¥", "\\":
+            typeBackSlash ? "\\" : "¥"
+        default:
+            text
+        }
+    }
+}
diff --git a/Core/Tests/CoreTests/InputUtilsTests/OptionDirectInputResolverTests.swift b/Core/Tests/CoreTests/InputUtilsTests/OptionDirectInputResolverTests.swift
new file mode 100644
index 0000000..97243f7
--- /dev/null
+++ b/Core/Tests/CoreTests/InputUtilsTests/OptionDirectInputResolverTests.swift
@@ -0,0 +1,83 @@
+import Core
+import Testing
+
+@Test func testOptionDirectInputResolverReturnsFullWidthTextForJapaneseNoneState() async throws {
+    let option: KeyEventCore.ModifierFlag = [.option]
+    let shiftOption: KeyEventCore.ModifierFlag = [.option, .shift]
+
+    #expect(OptionDirectInputResolver.resolve(
+        characters: "a",
+        modifierFlags: option,
+        inputLanguage: .japanese,
+        inputState: .none,
+        typeBackSlash: false
+    ) == "ａ")
+    #expect(OptionDirectInputResolver.resolve(
+        characters: "A",
+        modifierFlags: shiftOption,
+        inputLanguage: .japanese,
+        inputState: .none,
+        typeBackSlash: false
+    ) == "Ａ")
+    #expect(OptionDirectInputResolver.resolve(
+        characters: "-",
+        modifierFlags: option,
+        inputLanguage: .japanese,
+        inputState: .none,
+        typeBackSlash: false
+    ) == "－")
+    #expect(OptionDirectInputResolver.resolve(
+        characters: "/",
+        modifierFlags: shiftOption,
+        inputLanguage: .japanese,
+        inputState: .none,
+        typeBackSlash: false
+    ) == "／")
+    #expect(OptionDirectInputResolver.resolve(
+        characters: "¥",
+        modifierFlags: option,
+        inputLanguage: .japanese,
+        inputState: .none,
+        typeBackSlash: false
+    ) == "￥")
+    #expect(OptionDirectInputResolver.resolve(
+        characters: "¥",
+        modifierFlags: option,
+        inputLanguage: .japanese,
+        inputState: .none,
+        typeBackSlash: true
+    ) == "＼")
+}
+
+@Test func testOptionDirectInputResolverRejectsUnsupportedContext() async throws {
+    let option: KeyEventCore.ModifierFlag = [.option]
+
+    #expect(OptionDirectInputResolver.resolve(
+        characters: "a",
+        modifierFlags: [],
+        inputLanguage: .japanese,
+        inputState: .none,
+        typeBackSlash: false
+    ) == nil)
+    #expect(OptionDirectInputResolver.resolve(
+        characters: "a",
+        modifierFlags: option,
+        inputLanguage: .english,
+        inputState: .none,
+        typeBackSlash: false
+    ) == nil)
+    #expect(OptionDirectInputResolver.resolve(
+        characters: "a",
+        modifierFlags: option,
+        inputLanguage: .japanese,
+        inputState: .composing,
+        typeBackSlash: false
+    ) == nil)
+    #expect(OptionDirectInputResolver.resolve(
+        characters: "\r",
+        modifierFlags: option,
+        inputLanguage: .japanese,
+        inputState: .none,
+        typeBackSlash: false
+    ) == nil)
+}
diff --git a/azooKeyMac/InputController/azooKeyMacInputController.swift b/azooKeyMac/InputController/azooKeyMacInputController.swift
index c8cd83f..9f9bb91 100644
--- a/azooKeyMac/InputController/azooKeyMacInputController.swift
+++ b/azooKeyMac/InputController/azooKeyMacInputController.swift
@@ -255,14 +255,6 @@ class azooKeyMacInputController: IMKInputController, NSMenuItemValidation { // s
         self.appMenu
     }
 
-    private func isPrintable(_ text: String) -> Bool {
-        let printable: CharacterSet = [.alphanumerics, .symbols, .punctuationCharacters]
-            .reduce(into: CharacterSet()) {
-                $0.formUnion($1)
-            }
-        return CharacterSet(text.unicodeScalars).isSubset(of: printable)
-    }
-
     // swiftlint:disable:next cyclomatic_complexity
     @MainActor override func handle(_ event: NSEvent!, client sender: Any!) -> Bool {
         guard let event, let client = sender as? IMKTextInput else {
@@ -287,6 +279,20 @@ class azooKeyMacInputController: IMKInputController, NSMenuItemValidation { // s
             return true
         }
 
+        let eventModifiers = KeyEventCore.ModifierFlag(from: event.modifierFlags)
+        let charactersForOptionDirectInput = event.characters(byApplyingModifiers: event.modifierFlags.subtracting(.option))
+        if Config.OptionDirectFullWidthInput().value,
+           let text = OptionDirectInputResolver.resolve(
+            characters: charactersForOptionDirectInput,
+            modifierFlags: eventModifiers,
+            inputLanguage: inputLanguage,
+            inputState: inputState,
+            typeBackSlash: Config.TypeBackSlash().value
+           ) {
+            client.insertText(text, replacementRange: NSRange(location: NSNotFound, length: 0))
+            return true
+        }
+
         let userAction = UserAction.getUserAction(eventCore: event.keyEventCore, inputLanguage: inputLanguage)
 
         // 英数キー（keyCode 102）の処理
diff --git a/azooKeyMac/Windows/ConfigWindow.swift b/azooKeyMac/Windows/ConfigWindow.swift
index d5546b1..d9bcd4a 100644
--- a/azooKeyMac/Windows/ConfigWindow.swift
+++ b/azooKeyMac/Windows/ConfigWindow.swift
@@ -8,6 +8,7 @@ struct ConfigWindow: View {
     @ConfigState private var typeBackSlash = Config.TypeBackSlash()
     @ConfigState private var punctuationStyle = Config.PunctuationStyle()
     @ConfigState private var typeHalfSpace = Config.TypeHalfSpace()
+    @ConfigState private var optionDirectFullWidthInput = Config.OptionDirectFullWidthInput()
     @ConfigState private var zenzaiProfile = Config.ZenzaiProfile()
     @ConfigState private var zenzaiPersonalizationLevel = Config.ZenzaiPersonalizationLevel()
     @ConfigState private var openAiApiKey = Config.OpenAiApiKey()
@@ -473,6 +474,7 @@ struct ConfigWindow: View {
             Section {
                 Toggle("円記号の代わりにバックスラッシュを入力", isOn: $typeBackSlash)
                 Toggle("スペースは常に半角を入力", isOn: $typeHalfSpace)
+                Toggle("Optionキーで直接全角英数を入力", isOn: $optionDirectFullWidthInput)
                 Picker("句読点の種類", selection: $punctuationStyle) {
                     Text("、と。").tag(Config.PunctuationStyle.Value.`kutenAndToten`)
                     Text("、と．").tag(Config.PunctuationStyle.Value.periodAndToten)