diff --git a/packages/frontend/src/boot/common.ts b/packages/frontend/src/boot/common.ts
index 95ba278ff4..f9783cb65c 100644
--- a/packages/frontend/src/boot/common.ts
+++ b/packages/frontend/src/boot/common.ts
@@ -69,9 +69,6 @@ export async function common(createVue: () => Promise<App<Element>>) {
 	if (lastVersion !== version) {
 		miLocalStorage.setItem('lastVersion', version);
 
-		// テーマリビルドするため
-		miLocalStorage.removeItem('theme');
-
 		try { // 変なバージョン文字列来るとcompareVersionsでエラーになるため
 			if (lastVersion != null && compareVersions(version, lastVersion) === 1) {
 				isClientUpdated = true;
diff --git a/packages/frontend/src/local-storage.ts b/packages/frontend/src/local-storage.ts
index 687983bcdb..f79f62f80e 100644
--- a/packages/frontend/src/local-storage.ts
+++ b/packages/frontend/src/local-storage.ts
@@ -25,6 +25,7 @@ export type Keys = (
 	'bootloaderLocales' |
 	'theme' |
 	'themeId' |
+	'themeCachedVersion' |
 	'customCss' |
 	'chatMessageDrafts' |
 	'scratchpad' |
diff --git a/packages/frontend/src/theme.ts b/packages/frontend/src/theme.ts
index 7cbaf87243..13f5dbf60e 100644
--- a/packages/frontend/src/theme.ts
+++ b/packages/frontend/src/theme.ts
@@ -10,6 +10,7 @@ import tinycolor from 'tinycolor2';
 import lightTheme from '@@/themes/_light.json5';
 import darkTheme from '@@/themes/_dark.json5';
 import JSON5 from 'json5';
+import { version } from '@@/js/config.js';
 import type { Ref } from 'vue';
 import type { BundledTheme } from 'shiki/themes';
 import { deepClone } from '@/utility/clone.js';
@@ -123,6 +124,7 @@ function applyThemeInternal(theme: Theme, persist: boolean) {
 	if (persist) {
 		miLocalStorage.setItem('theme', JSON.stringify(props));
 		miLocalStorage.setItem('themeId', theme.id);
+		miLocalStorage.setItem('themeCachedVersion', version);
 		miLocalStorage.setItem('colorScheme', colorScheme);
 	}
 
@@ -139,7 +141,7 @@ export function applyTheme(theme: Theme, persist = true) {
 		timeout = null;
 	}
 
-	if (theme.id === currentThemeId) return;
+	if (theme.id === currentThemeId && miLocalStorage.getItem('themeCachedVersion') === version) return;
 	currentThemeId = theme.id;
 
 	if (window.document.startViewTransition != null) {