diff --git a/desktop/src/components/browser/BrowserAddressBar.test.tsx b/desktop/src/components/browser/BrowserAddressBar.test.tsx
index c82beed7..e6c6cc3a 100644
--- a/desktop/src/components/browser/BrowserAddressBar.test.tsx
+++ b/desktop/src/components/browser/BrowserAddressBar.test.tsx
@@ -34,4 +34,16 @@ describe('BrowserAddressBar', () => {
     fireEvent.click(screen.getByLabelText('后退'))
     expect(onBack).toHaveBeenCalled()
   })
+
+  it('shows the loading progress bar and a busy reload button while loading', () => {
+    render(<BrowserAddressBar {...baseProps} loading />)
+    expect(screen.getByTestId('browser-loading-bar')).toBeInTheDocument()
+    expect(screen.getByLabelText('刷新')).toHaveAttribute('aria-busy', 'true')
+  })
+
+  it('hides the loading progress bar when not loading', () => {
+    render(<BrowserAddressBar {...baseProps} loading={false} />)
+    expect(screen.queryByTestId('browser-loading-bar')).not.toBeInTheDocument()
+    expect(screen.getByLabelText('刷新')).toHaveAttribute('aria-busy', 'false')
+  })
 })
diff --git a/desktop/src/components/browser/BrowserAddressBar.tsx b/desktop/src/components/browser/BrowserAddressBar.tsx
index 37776bc6..05b34095 100644
--- a/desktop/src/components/browser/BrowserAddressBar.tsx
+++ b/desktop/src/components/browser/BrowserAddressBar.tsx
@@ -1,25 +1,28 @@
 import { useEffect, useState } from 'react'
-import { ArrowLeft, ArrowRight, RotateCw } from 'lucide-react'
+import { ArrowLeft, ArrowRight, Loader2, RotateCw } from 'lucide-react'
 
 type Props = {
   url: string
   canGoBack: boolean
   canGoForward: boolean
+  loading?: boolean
   onNavigate: (url: string) => void
   onBack: () => void
   onForward: () => void
   onReload: () => void
 }
 
-export function BrowserAddressBar({ url, canGoBack, canGoForward, onNavigate, onBack, onForward, onReload }: Props) {
+export function BrowserAddressBar({ url, canGoBack, canGoForward, loading = false, onNavigate, onBack, onForward, onReload }: Props) {
   const [draft, setDraft] = useState(url)
   useEffect(() => { setDraft(url) }, [url])
 
   return (
-    <div className="flex items-center gap-1 px-2 py-1.5 border-b border-[var(--color-border)]">
+    <div className="relative flex items-center gap-1 px-2 py-1.5 border-b border-[var(--color-border)]">
       <button aria-label="后退" disabled={!canGoBack} onClick={onBack} className="p-1 disabled:opacity-40"><ArrowLeft size={16} /></button>
       <button aria-label="前进" disabled={!canGoForward} onClick={onForward} className="p-1 disabled:opacity-40"><ArrowRight size={16} /></button>
-      <button aria-label="刷新" onClick={onReload} className="p-1"><RotateCw size={16} /></button>
+      <button aria-label="刷新" aria-busy={loading} onClick={onReload} className="p-1">
+        {loading ? <Loader2 size={16} className="animate-spin" /> : <RotateCw size={16} />}
+      </button>
       <form className="flex-1" onSubmit={(e) => { e.preventDefault(); onNavigate(draft.trim()) }}>
         <input
           className="w-full rounded-md bg-[var(--color-surface)] px-2 py-1 text-xs text-[var(--color-text-primary)]"
@@ -28,6 +31,14 @@ export function BrowserAddressBar({ url, canGoBack, canGoForward, onNavigate, on
           spellCheck={false}
         />
       </form>
+      {loading && (
+        <div
+          role="progressbar"
+          aria-label="加载中"
+          data-testid="browser-loading-bar"
+          className="progress-indeterminate-track pointer-events-none absolute inset-x-0 bottom-0 h-0.5"
+        />
+      )}
     </div>
   )
 }
diff --git a/desktop/src/components/browser/BrowserSurface.test.tsx b/desktop/src/components/browser/BrowserSurface.test.tsx
index ae4baa80..9d829608 100644
--- a/desktop/src/components/browser/BrowserSurface.test.tsx
+++ b/desktop/src/components/browser/BrowserSurface.test.tsx
@@ -61,4 +61,43 @@ describe('BrowserSurface', () => {
     expect(useBrowserPanelStore.getState().bySession['s1']!.pickerActive).toBe(false)
     expect(bridge.eval).toHaveBeenLastCalledWith(expect.stringContaining('exit-picker'))
   })
+
+  it('renders the loading indicator while the session is loading (open starts loading)', () => {
+    useBrowserPanelStore.getState().open('s1', 'http://localhost:5173/')
+    render(<BrowserSurface sessionId="s1" />)
+    expect(screen.getByTestId('browser-loading-bar')).toBeInTheDocument()
+    expect(screen.getByLabelText('刷新')).toHaveAttribute('aria-busy', 'true')
+  })
+
+  it('hides the loading indicator once the page is ready', () => {
+    useBrowserPanelStore.getState().open('s1', 'http://localhost:5173/')
+    useBrowserPanelStore.getState().setReady('s1')
+    render(<BrowserSurface sessionId="s1" />)
+    expect(screen.queryByTestId('browser-loading-bar')).not.toBeInTheDocument()
+    expect(screen.getByLabelText('刷新')).toHaveAttribute('aria-busy', 'false')
+  })
+
+  it('reload flips the session back into loading and shows the indicator', () => {
+    useBrowserPanelStore.getState().open('s1', 'http://localhost:5173/')
+    useBrowserPanelStore.getState().setReady('s1')
+    render(<BrowserSurface sessionId="s1" />)
+    expect(screen.queryByTestId('browser-loading-bar')).not.toBeInTheDocument()
+    fireEvent.click(screen.getByLabelText('刷新'))
+    expect(useBrowserPanelStore.getState().bySession['s1']!.loading).toBe(true)
+    expect(bridge.navigate).toHaveBeenCalledWith('http://localhost:5173/')
+    expect(screen.getByTestId('browser-loading-bar')).toBeInTheDocument()
+  })
+
+  it('forces loading off after the timeout fallback elapses', () => {
+    vi.useFakeTimers()
+    try {
+      useBrowserPanelStore.getState().open('s1', 'http://localhost:5173/')
+      render(<BrowserSurface sessionId="s1" />)
+      expect(useBrowserPanelStore.getState().bySession['s1']!.loading).toBe(true)
+      vi.advanceTimersByTime(15000)
+      expect(useBrowserPanelStore.getState().bySession['s1']!.loading).toBe(false)
+    } finally {
+      vi.useRealTimers()
+    }
+  })
 })
diff --git a/desktop/src/components/browser/BrowserSurface.tsx b/desktop/src/components/browser/BrowserSurface.tsx
index ef55a1c9..0ab181cb 100644
--- a/desktop/src/components/browser/BrowserSurface.tsx
+++ b/desktop/src/components/browser/BrowserSurface.tsx
@@ -44,6 +44,17 @@ export function BrowserSurface({ sessionId }: { sessionId: string }) {
 
   useEffect(() => () => { previewBridge.setVisible(false) }, [])
 
+  // 兜底：navigated/ready 依赖注入脚本，若外站 CSP 拦截则永不回灌。loading 变 true 后 ~15s 强制收尾。
+  const isLoading = session?.loading ?? false
+  const currentUrl = session?.url
+  useEffect(() => {
+    if (!isLoading) return
+    const timer = window.setTimeout(() => {
+      useBrowserPanelStore.getState().setLoading(sessionId, false)
+    }, 15000)
+    return () => window.clearTimeout(timer)
+  }, [isLoading, currentUrl, sessionId])
+
   if (!session) return null
 
   return (
@@ -52,10 +63,11 @@ export function BrowserSurface({ sessionId }: { sessionId: string }) {
         url={session.url}
         canGoBack={session.canGoBack}
         canGoForward={session.canGoForward}
+        loading={session.loading}
         onNavigate={(url) => { store.navigate(sessionId, url); previewBridge.navigate(url) }}
-        onBack={() => { store.goBack(sessionId); previewBridge.navigate(useBrowserPanelStore.getState().bySession[sessionId]!.url) }}
-        onForward={() => { store.goForward(sessionId); previewBridge.navigate(useBrowserPanelStore.getState().bySession[sessionId]!.url) }}
-        onReload={() => previewBridge.navigate(session.url)}
+        onBack={() => { store.goBack(sessionId); store.setLoading(sessionId, true); previewBridge.navigate(useBrowserPanelStore.getState().bySession[sessionId]!.url) }}
+        onForward={() => { store.goForward(sessionId); store.setLoading(sessionId, true); previewBridge.navigate(useBrowserPanelStore.getState().bySession[sessionId]!.url) }}
+        onReload={() => { store.setLoading(sessionId, true); previewBridge.navigate(session.url) }}
       />
       <div className="flex items-center gap-1 border-b px-2 py-1">
         <button
diff --git a/desktop/src/stores/browserPanelStore.test.ts b/desktop/src/stores/browserPanelStore.test.ts
index 25782a86..94374942 100644
--- a/desktop/src/stores/browserPanelStore.test.ts
+++ b/desktop/src/stores/browserPanelStore.test.ts
@@ -49,12 +49,37 @@ describe('browserPanelStore', () => {
     expect(useBrowserPanelStore.getState().bySession['s1']!.pickerActive).toBe(true)
   })
 
-  it('setNavigated updates url/title without growing history', () => {
+  it('open starts a session in the loading state', () => {
+    useBrowserPanelStore.getState().open('s1', 'http://localhost/a')
+    expect(useBrowserPanelStore.getState().bySession['s1']!.loading).toBe(true)
+  })
+
+  it('navigate flips loading back on', () => {
+    const st = useBrowserPanelStore.getState()
+    st.open('s1', 'http://localhost/a')
+    st.setReady('s1') // simulate the page finishing the first load
+    expect(useBrowserPanelStore.getState().bySession['s1']!.loading).toBe(false)
+    st.navigate('s1', 'http://localhost/b')
+    expect(useBrowserPanelStore.getState().bySession['s1']!.loading).toBe(true)
+  })
+
+  it('setNavigated clears loading and updates url/title without growing history', () => {
     const st = useBrowserPanelStore.getState()
     st.open('s1', 'http://x/a')
+    expect(useBrowserPanelStore.getState().bySession['s1']!.loading).toBe(true)
     st.setNavigated('s1', 'http://x/b', 'B')
     const s = useBrowserPanelStore.getState().bySession['s1']!
     expect(s.url).toBe('http://x/b')
     expect(s.title).toBe('B')
+    expect(s.loading).toBe(false)
+    expect(s.history).toEqual(['http://x/a'])
+  })
+
+  it('setReady clears loading', () => {
+    const st = useBrowserPanelStore.getState()
+    st.open('s1', 'http://x/a')
+    expect(useBrowserPanelStore.getState().bySession['s1']!.loading).toBe(true)
+    st.setReady('s1')
+    expect(useBrowserPanelStore.getState().bySession['s1']!.loading).toBe(false)
   })
 })
diff --git a/desktop/src/stores/browserPanelStore.ts b/desktop/src/stores/browserPanelStore.ts
index f17f0a03..d89da2a7 100644
--- a/desktop/src/stores/browserPanelStore.ts
+++ b/desktop/src/stores/browserPanelStore.ts
@@ -40,12 +40,12 @@ const withNav = (s: BrowserSessionState): BrowserSessionState => ({
 export const useBrowserPanelStore = create<BrowserPanelState>((set) => ({
   bySession: {},
   open: (sessionId, url) => set((st) => ({
-    bySession: { ...st.bySession, [sessionId]: empty(url) },
+    bySession: { ...st.bySession, [sessionId]: { ...empty(url), loading: true } },
   })),
   navigate: (sessionId, url) => set((st) => {
     const cur = st.bySession[sessionId] ?? empty(url)
     const history = [...cur.history.slice(0, cur.historyIndex + 1), url]
-    return { bySession: { ...st.bySession, [sessionId]: withNav({ ...cur, isOpen: true, history, historyIndex: history.length - 1 }) } }
+    return { bySession: { ...st.bySession, [sessionId]: withNav({ ...cur, isOpen: true, loading: true, history, historyIndex: history.length - 1 }) } }
   }),
   goBack: (sessionId) => set((st) => {
     const cur = st.bySession[sessionId]; if (!cur || cur.historyIndex <= 0) return st
diff --git a/desktop/src/theme/globals.css b/desktop/src/theme/globals.css
index f03e0402..8ed50c0b 100644
--- a/desktop/src/theme/globals.css
+++ b/desktop/src/theme/globals.css
@@ -1281,3 +1281,32 @@ button, input, textarea, select, a, [role="button"] {
 @keyframes progress-fill {
   from { width: 0%; }
 }
+
+/* Indeterminate (browser-style) loading bar: a segment that slides across the track */
+@keyframes progress-indeterminate {
+  0% { left: -40%; right: 100%; }
+  60% { left: 100%; right: -40%; }
+  100% { left: 100%; right: -40%; }
+}
+.progress-indeterminate-track {
+  position: relative;
+  overflow: hidden;
+}
+.progress-indeterminate-track::before {
+  content: '';
+  position: absolute;
+  top: 0;
+  bottom: 0;
+  left: -40%;
+  right: 100%;
+  background: var(--color-primary);
+  animation: progress-indeterminate 1.1s ease-in-out infinite;
+}
+@media (prefers-reduced-motion: reduce) {
+  .progress-indeterminate-track::before {
+    animation: none;
+    left: 0;
+    right: 0;
+    opacity: 0.5;
+  }
+}