diff --git a/src/lib/components/layout/ImportChatsModal.svelte b/src/lib/components/layout/ImportChatsModal.svelte
index 30ca84863b..30302bc650 100644
--- a/src/lib/components/layout/ImportChatsModal.svelte
+++ b/src/lib/components/layout/ImportChatsModal.svelte
@@ -173,10 +173,10 @@
 			<div>
 				<div class="text-lg font-semibold text-gray-900 dark:text-white flex items-center gap-2">
 					<span class="w-3 h-3 rounded bg-blue-500 shadow-[0_0_8px_rgba(59,130,246,0.6)]"></span>
-					Chat Filter & Import
+					记录筛选与导入
 				</div>
 				<div class="text-sm text-gray-500 dark:text-gray-400 mt-1">
-					导入 JSON 数组，筛选所需的聊天记录，自动下载并导入。
+					筛选所需的聊天记录
 				</div>
 			</div>
 			<button
@@ -191,7 +191,7 @@
 		<div class="space-y-4">
 			<div class="rounded-2xl border border-gray-100 dark:border-gray-800 bg-white dark:bg-gray-900 p-4 space-y-3">
 				<div class="flex items-center justify-between">
-					<div class="text-sm font-semibold text-gray-800 dark:text-gray-100">1. 读取文件 (JSON Array)</div>
+					<div class="text-sm font-semibold text-gray-800 dark:text-gray-100">1. 读取文件</div>
 				</div>
 
 				<div
diff --git a/src/lib/i18n/index.ts b/src/lib/i18n/index.ts
index e5c2d183b2..3425df48d9 100644
--- a/src/lib/i18n/index.ts
+++ b/src/lib/i18n/index.ts
@@ -41,7 +41,7 @@ export const initI18n = (defaultLocale?: string | undefined) => {
 	const detectionOrder = defaultLocale
 		? ['querystring', 'localStorage']
 		: ['querystring', 'localStorage', 'navigator'];
-	const fallbackDefaultLocale = defaultLocale ? [defaultLocale] : ['en-US'];
+	const fallbackDefaultLocale = defaultLocale ? [defaultLocale] : ['zh-CN'];
 
 	const loadResource = (language: string, namespace: string) =>
 		import(`./locales/${language}/${namespace}.json`);
@@ -67,7 +67,7 @@ export const initI18n = (defaultLocale?: string | undefined) => {
 			}
 		});
 
-	const lang = i18next?.language || defaultLocale || 'en-US';
+	const lang = i18next?.language || defaultLocale || 'zh-CN';
 	document.documentElement.setAttribute('lang', lang);
 };
 
diff --git a/src/routes/+layout.svelte b/src/routes/+layout.svelte
index bbdd5a60b4..03b1039c7a 100644
--- a/src/routes/+layout.svelte
+++ b/src/routes/+layout.svelte
@@ -602,7 +602,7 @@
 		// Initialize i18n even if we didn't get a backend config,
 		// so `/error` can show something that's not `undefined`.
 
-		initI18n(localStorage?.locale);
+		initI18n(localStorage?.locale ?? 'zh-CN');
 		if (!localStorage.locale) {
 			const languages = await getLanguages();
 			const browserLanguages = navigator.languages
@@ -610,7 +610,7 @@
 				: [navigator.language || navigator.userLanguage];
 			const lang = backendConfig.default_locale
 				? backendConfig.default_locale
-				: bestMatchingLanguage(languages, browserLanguages, 'en-US');
+				: bestMatchingLanguage(languages, browserLanguages, 'zh-CN');
 			changeLanguage(lang);
 		}