diff --git a/src/lib/__tests__/dweb-update.test.ts b/src/lib/__tests__/dweb-update.test.ts
index 011d0b206..008bed1b9 100644
--- a/src/lib/__tests__/dweb-update.test.ts
+++ b/src/lib/__tests__/dweb-update.test.ts
@@ -9,6 +9,7 @@ type FetchResponse = {
 
 function stubGlobals() {
   vi.stubGlobal('__KEYAPP_SITE_ORIGIN__', 'https://example.com/KeyApp/')
+  vi.stubGlobal('__KEYAPP_BASE_URL__', './')
   vi.stubGlobal('__DEV_MODE__', false)
   vi.stubGlobal('__APP_VERSION__', '1.2.3')
   Object.defineProperty(window, '__native_close_watcher_kit__', {
@@ -33,6 +34,13 @@ describe('dweb update', () => {
     expect(url).toBe('https://example.com/KeyApp/dweb-dev/metadata.json')
   })
 
+  it('resolves metadata url with base url when origin has no path', () => {
+    vi.stubGlobal('__KEYAPP_SITE_ORIGIN__', 'https://example.com')
+    vi.stubGlobal('__KEYAPP_BASE_URL__', '/KeyApp/')
+    const url = resolveDwebMetadataUrl()
+    expect(url).toBe('https://example.com/KeyApp/dweb/metadata.json')
+  })
+
   it('builds install url', () => {
     const url = resolveInstallUrl('https://example.com/KeyApp/dweb/metadata.json')
     expect(url).toBe('dweb://install?url=https%3A%2F%2Fexample.com%2FKeyApp%2Fdweb%2Fmetadata.json')
diff --git a/src/lib/dweb-update.ts b/src/lib/dweb-update.ts
index 4f9c43e46..153ea6f8d 100644
--- a/src/lib/dweb-update.ts
+++ b/src/lib/dweb-update.ts
@@ -68,8 +68,29 @@ function normalizeOrigin(origin: string): string {
   return origin.endsWith('/') ? origin : `${origin}/`
 }
 
+function normalizeBasePath(basePath: string): string {
+  if (!basePath) return './'
+  return basePath.endsWith('/') ? basePath : `${basePath}/`
+}
+
+function resolveSiteBase(): string {
+  const origin = normalizeOrigin(__KEYAPP_SITE_ORIGIN__)
+  try {
+    const originUrl = new URL(origin)
+    const originPath = originUrl.pathname
+    if (originPath && originPath !== '/') {
+      return normalizeOrigin(origin)
+    }
+  } catch {
+    return origin
+  }
+
+  const basePath = normalizeBasePath(__KEYAPP_BASE_URL__)
+  return normalizeOrigin(new URL(basePath, origin).toString())
+}
+
 export function resolveDwebMetadataUrl(): string {
-  const base = normalizeOrigin(__KEYAPP_SITE_ORIGIN__)
+  const base = resolveSiteBase()
   const path = __DEV_MODE__ ? 'dweb-dev/metadata.json' : 'dweb/metadata.json'
   return new URL(path, base).toString()
 }
diff --git a/src/vite-env.d.ts b/src/vite-env.d.ts
index b096129b1..1cf4f5ed0 100644
--- a/src/vite-env.d.ts
+++ b/src/vite-env.d.ts
@@ -14,6 +14,9 @@ declare global {
   /** KeyApp 官网 Origin - 通过 vite.config.ts define 配置 */
   const __KEYAPP_SITE_ORIGIN__: string
 
+  /** KeyApp Base URL - 通过 vite.config.ts define 配置 */
+  const __KEYAPP_BASE_URL__: string
+
   /** 默认生态源列表 - 通过 vite.config.ts define 配置 */
   const __ECOSYSTEM_SOURCES__: Array<{ name: string; url: string; icon?: string }>
 
diff --git a/vite.config.ts b/vite.config.ts
index 0f52c2f19..8e1f72f37 100644
--- a/vite.config.ts
+++ b/vite.config.ts
@@ -209,6 +209,8 @@ export default defineConfig(({ mode }) => {
       __APP_VERSION__: JSON.stringify(appVersion),
       // KeyApp 官网 Origin（DWEB 升级检查使用）
       __KEYAPP_SITE_ORIGIN__: JSON.stringify(siteOrigin),
+      // KeyApp Base URL（DWEB 升级链接拼接使用）
+      __KEYAPP_BASE_URL__: JSON.stringify(BASE_URL),
       // 默认生态源列表（用于订阅源管理展示）
       __ECOSYSTEM_SOURCES__: JSON.stringify(ecosystemSources),
       // API Keys 对象（用于动态读取环境变量）