diff --git a/web/package.json b/web/package.json
index e51d4da..54521aa 100644
--- a/web/package.json
+++ b/web/package.json
@@ -6,6 +6,7 @@
   "dependencies": {
     "@douyinfe/semi-icons": "^2.63.1",
     "@douyinfe/semi-illustrations": "^2.100.0",
+    "@douyinfe/semi-theme-default": "^2.101.0",
     "@douyinfe/semi-ui": "^2.69.1",
     "@lobehub/icons": "^2.0.0",
     "@visactor/react-vchart": "~1.8.8",
diff --git a/web/src/components/layout/headerbar/ActionButtons.jsx b/web/src/components/layout/headerbar/ActionButtons.jsx
index 8fcf012..8346575 100644
--- a/web/src/components/layout/headerbar/ActionButtons.jsx
+++ b/web/src/components/layout/headerbar/ActionButtons.jsx
@@ -36,6 +36,7 @@ const ActionButtons = ({
   isMobile,
   isSelfUseMode,
   showThemeToggle = true,
+  // 默认隐藏顶栏语言选择器，仅保留简体中文
   showLanguageSelector = false,
   logout,
   navigate,
diff --git a/web/src/components/settings/PersonalSetting.jsx b/web/src/components/settings/PersonalSetting.jsx
index d665b31..dcc3b3a 100644
--- a/web/src/components/settings/PersonalSetting.jsx
+++ b/web/src/components/settings/PersonalSetting.jsx
@@ -597,7 +597,7 @@ const PersonalSetting = () => {
                 onPasskeyDelete={handleRemovePasskey}
               />
 
-              {/* 偏好设置（语言等）- 已隐藏 */}
+              {/* 偏好设置（语言等）- 已隐藏：多语言功能屏蔽，统一使用简体中文 */}
               {/* <PreferencesSettings t={t} /> */}
             </div>
 
diff --git a/web/src/context/Theme/index.jsx b/web/src/context/Theme/index.jsx
index bdd5a65..300bd04 100644
--- a/web/src/context/Theme/index.jsx
+++ b/web/src/context/Theme/index.jsx
@@ -47,9 +47,9 @@ const getSystemTheme = () => {
 export const ThemeProvider = ({ children }) => {
   const [theme, _setTheme] = useState(() => {
     try {
-      return localStorage.getItem('theme-mode') || 'auto';
+      return localStorage.getItem('theme-mode-v2') || 'light';
     } catch {
-      return 'auto';
+      return 'light';
     }
   });
 
@@ -101,7 +101,7 @@ export const ThemeProvider = ({ children }) => {
     }
 
     _setTheme(themeValue);
-    localStorage.setItem('theme-mode', themeValue);
+    localStorage.setItem('theme-mode-v2', themeValue);
   }, []);
 
   return (
diff --git a/web/src/hooks/common/useHeaderBar.js b/web/src/hooks/common/useHeaderBar.js
index eb28cee..2a77f71 100644
--- a/web/src/hooks/common/useHeaderBar.js
+++ b/web/src/hooks/common/useHeaderBar.js
@@ -107,8 +107,9 @@ export const useHeaderBar = ({ onMobileMenuToggle, drawerOpen }) => {
 
   const isConsoleRoute = location.pathname.startsWith('/console');
 
-  // 读取顶栏主题切换和语言选择器开关配置
+  // 读取顶栏主题切换开关，语言选择器已强制关闭（仅保留简体中文）
   const showThemeToggle = statusState?.status?.HeaderShowThemeToggle !== false;
+  // 多语言切换已屏蔽，后端 HeaderShowLanguageSelector 开关不再生效
   const showLanguageSelector = false;
 
   const theme = useTheme();