diff --git a/backend/app/api/settings.py b/backend/app/api/settings.py
index 5f16834..deac8a1 100644
--- a/backend/app/api/settings.py
+++ b/backend/app/api/settings.py
@@ -58,6 +58,7 @@ def get_settings() -> dict:
         "has_ai_key": bool(secrets_store.get_ai_key()),
         "ai_model": secrets_store.get_ai_config("ai_model", settings.ai_model),
         "ai_daily_token_budget": int(secrets_store.get_ai_config("ai_daily_token_budget", str(settings.ai_daily_token_budget)) or settings.ai_daily_token_budget),
+        "ai_user_agent": secrets_store.get_ai_config("ai_user_agent", settings.ai_user_agent),
     }
 
 
@@ -212,6 +213,7 @@ class AiSettingsIn(BaseModel):
     api_key: str | None = None
     model: str = ""
     daily_token_budget: int = 500_000
+    user_agent: str = ""
 
 
 @router.post("/ai")
@@ -238,6 +240,9 @@ def save_ai_settings(req: AiSettingsIn) -> dict:
         settings.ai_model = req.model
     updates["ai_daily_token_budget"] = req.daily_token_budget
     settings.ai_daily_token_budget = req.daily_token_budget
+    # user_agent 允许清空(回到默认浏览器 UA),故无条件持久化
+    updates["ai_user_agent"] = req.user_agent
+    settings.ai_user_agent = req.user_agent
 
     if updates:
         secrets_store.save(updates)
diff --git a/backend/app/api/strategy.py b/backend/app/api/strategy.py
index dae6ddc..205784b 100644
--- a/backend/app/api/strategy.py
+++ b/backend/app/api/strategy.py
@@ -324,7 +324,12 @@ async def ai_test(request: Request):
         return {"ok": False, "error": "未配置 API Key"}
 
     try:
-        client = AsyncOpenAI(api_key=ai_key, base_url=settings.ai_base_url)
+        # User-Agent: 默认浏览器标识,绕过 Cloudflare 等 CDN/WAF 的 Bot 拦截(Issue #8)。
+        client = AsyncOpenAI(
+            api_key=ai_key,
+            base_url=settings.ai_base_url,
+            default_headers={"User-Agent": settings.ai_user_agent or "Mozilla/5.0"},
+        )
         resp = await client.chat.completions.create(
             model=settings.ai_model,
             messages=[{"role": "user", "content": "回复 OK"}],
diff --git a/backend/app/config.py b/backend/app/config.py
index 2dcfe8b..922410d 100644
--- a/backend/app/config.py
+++ b/backend/app/config.py
@@ -71,6 +71,13 @@ class Settings(BaseSettings):
     ai_api_key: str = ""
     ai_model: str = "gpt-5.5"
     ai_daily_token_budget: int = 5_000_000
+    # 默认浏览器风格 UA,绕过 Cloudflare 等 CDN/WAF 的 Bot 拦截(Issue #8)。
+    # 用户可在 AI 设置页按需修改。
+    ai_user_agent: str = (
+        "Mozilla/5.0 (Windows NT 10.0; Win64; x64) "
+        "AppleWebKit/537.36 (KHTML, like Gecko) "
+        "Chrome/131.0.0.0 Safari/537.36"
+    )
 
     # Server
     host: str = "0.0.0.0"
diff --git a/backend/app/strategy/ai_generator.py b/backend/app/strategy/ai_generator.py
index 38fa054..f774a4c 100644
--- a/backend/app/strategy/ai_generator.py
+++ b/backend/app/strategy/ai_generator.py
@@ -83,11 +83,17 @@ class AIStrategyGenerator:
         if not ai_key:
             raise RuntimeError("AI API Key 未配置，请在设置页面配置")
 
+        # User-Agent: 默认浏览器标识,绕过 Cloudflare 等 CDN/WAF 的 Bot 拦截(Issue #8)。
+        # 用户可在 AI 设置页自定义。
+        from app.config import settings
+        user_agent = secrets_store.get_ai_config("ai_user_agent", "") or settings.ai_user_agent
+
         client = AsyncOpenAI(
             api_key=ai_key,
             base_url=secrets_store.get_ai_config("ai_base_url", "https://api.alysc.top"),
             timeout=180.0,
             max_retries=2,
+            default_headers={"User-Agent": user_agent},
         )
         # 使用流式请求：CDN 收到首个 token 后会持续转发，不会因等待超时
         stream = await client.chat.completions.create(
diff --git a/frontend/src/lib/api.ts b/frontend/src/lib/api.ts
index baddeed..72a4e00 100644
--- a/frontend/src/lib/api.ts
+++ b/frontend/src/lib/api.ts
@@ -566,6 +566,7 @@ export interface SettingsState {
   has_ai_key: boolean
   ai_model: string
   ai_daily_token_budget: number
+  ai_user_agent: string
 }
 
 /** 保存 TickFlow Key 的响应(先探后存) */
@@ -636,7 +637,7 @@ export const api = {
     ),
 
   /** 保存 AI 配置 */
-  saveAiSettings: (ai: { provider?: string; base_url?: string; api_key?: string; model?: string; daily_token_budget?: number }) =>
+  saveAiSettings: (ai: { provider?: string; base_url?: string; api_key?: string; model?: string; daily_token_budget?: number; user_agent?: string }) =>
     request<{ ok: boolean }>('/api/settings/ai', {
       method: 'POST',
       body: JSON.stringify(ai),
diff --git a/frontend/src/pages/settings/AI.tsx b/frontend/src/pages/settings/AI.tsx
index 2bfbeba..4e75385 100644
--- a/frontend/src/pages/settings/AI.tsx
+++ b/frontend/src/pages/settings/AI.tsx
@@ -1,6 +1,6 @@
 import { useState, useEffect } from 'react'
 import { useMutation, useQueryClient } from '@tanstack/react-query'
-import { Save, Loader2, Check, Wifi, WifiOff, Eye, EyeOff, Shield } from 'lucide-react'
+import { Save, Loader2, Check, Wifi, WifiOff, Eye, EyeOff, Shield, Shuffle } from 'lucide-react'
 import { useSettings } from '@/lib/useSharedQueries'
 import { api } from '@/lib/api'
 import { QK } from '@/lib/queryKeys'
@@ -21,6 +21,10 @@ export function SettingsAIPanel() {
   const [apiKey, setApiKey] = useState('')
   const [model, setModel] = useState('')
   const [tokenBudget, setTokenBudget] = useState(5_000_000)
+  // 自定义 User-Agent 开关:关闭 → 后端用内置默认浏览器 UA(开箱绕过 CDN 拦截);
+  // 开启 → 用下方文本框的 UA,留空时随机生成。
+  const [customUa, setCustomUa] = useState(false)
+  const [userAgent, setUserAgent] = useState('')
   const [showKey, setShowKey] = useState(false)
   const [saved, setSaved] = useState(false)
 
@@ -28,17 +32,35 @@ export function SettingsAIPanel() {
   const [testing, setTesting] = useState(false)
   const [testResult, setTestResult] = useState<{ ok: boolean; msg: string } | null>(null)
 
+  // 随机生成一个近期桌面端 Chrome UA(Win/Mac/Linux 随机)
+  const genRandomUa = () => {
+    const major = 128 + Math.floor(Math.random() * 8) // 128~135
+    const platforms = [
+      `Windows NT 10.0; Win64; x64`,
+      `Macintosh; Intel Mac OS X 10_15_7`,
+      `X11; Linux x86_64`,
+    ]
+    const pf = platforms[Math.floor(Math.random() * platforms.length)]
+    setUserAgent(`Mozilla/5.0 (${pf}) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/${major}.0.0.0 Safari/537.36`)
+  }
+
   useEffect(() => {
     if (!s) return
     setProvider(s.ai_provider ?? 'openai_compat')
     setBaseUrl(s.ai_base_url ?? '')
     setModel(s.ai_model ?? '')
     setTokenBudget(s.ai_daily_token_budget ?? 500_000)
+    // 有已保存的自定义 UA → 开关默认开启;否则关闭(用后端内置默认)
+    const ua = s.ai_user_agent ?? ''
+    setCustomUa(!!ua)
+    setUserAgent(ua)
   }, [s])
 
   const save = useMutation({
     mutationFn: () => api.saveAiSettings({
       provider, base_url: baseUrl, api_key: apiKey || undefined, model, daily_token_budget: tokenBudget,
+      // 关闭开关 → 提交空串,后端回退内置默认 UA
+      user_agent: customUa ? userAgent : '',
     }),
     onSuccess: () => {
       setSaved(true); setApiKey(''); qc.invalidateQueries({ queryKey: QK.settings })
@@ -50,7 +72,7 @@ export function SettingsAIPanel() {
     setTesting(true); setTestResult(null)
     try {
       // 先保存当前配置（不保存 Key 仅用于测试时临时存）
-      if (apiKey) await api.saveAiSettings({ provider, base_url: baseUrl, api_key: apiKey, model, daily_token_budget: tokenBudget })
+      if (apiKey) await api.saveAiSettings({ provider, base_url: baseUrl, api_key: apiKey, model, daily_token_budget: tokenBudget, user_agent: customUa ? userAgent : '' })
       const r = await api.strategyAiTest()
       setTestResult({ ok: r.ok, msg: r.ok ? `连通成功 · 模型: ${r.model}${r.usage ? ` · 消耗 ${r.usage.prompt + r.usage.completion} tokens` : ''}` : (r.error ?? '未知错误') })
     } catch (e: any) {
@@ -178,6 +200,39 @@ export function SettingsAIPanel() {
               <span className="text-[10px] text-muted">超出后仅发出提醒，不阻止 AI 调用</span>
             </div>
           </div>
+
+          {/* 请求头 User-Agent */}
+          <div className="space-y-2">
+            <div className="flex items-center justify-between">
+              <label className="text-[10px] text-muted/50 uppercase tracking-wider">自定义请求头 User-Agent</label>
+              <button
+                type="button"
+                onClick={() => setCustomUa(v => !v)}
+                className={`relative inline-flex h-5 w-9 items-center rounded-full shrink-0 transition-colors duration-200 ${customUa ? 'bg-accent' : 'bg-elevated'}`}
+                aria-pressed={customUa}
+              >
+                <span className={`inline-block h-3.5 w-3.5 rounded-full bg-white shadow-sm transition-transform duration-200 ${customUa ? 'translate-x-[18px]' : 'translate-x-[3px]'}`} />
+              </button>
+            </div>
+            <div className="text-[10px] text-muted/70 leading-relaxed">
+              {customUa
+                ? '当前使用下方自定义 UA 调用 AI API。'
+                : '默认已使用内置浏览器标识，可绕过 Cloudflare 等 CDN/WAF 拦截。仅在默认标识被拦截时才需开启自定义。'}
+            </div>
+            {customUa && (
+              <div className="flex gap-2">
+                <input type="text" value={userAgent} onChange={e => setUserAgent(e.target.value)}
+                  placeholder="留空点击「随机生成」或直接粘贴浏览器 UA"
+                  className="flex-1 h-8 px-2.5 rounded-lg bg-base border-0 ring-1 ring-border/30 text-xs font-mono text-foreground placeholder:text-muted/30 focus:outline-none focus:ring-2 focus:ring-accent/30 transition-shadow" />
+                <button type="button" onClick={() => { if (!userAgent) genRandomUa() }}
+                  title={userAgent ? '已存在内容，清空后可重新生成' : '随机生成浏览器 UA'}
+                  className="h-8 px-2.5 rounded-lg border border-border/50 text-xs text-secondary hover:text-accent hover:border-accent/30 transition-all flex items-center gap-1.5 shrink-0 disabled:opacity-40"
+                  disabled={!!userAgent}>
+                  <Shuffle className="h-3 w-3" /> 随机
+                </button>
+              </div>
+            )}
+          </div>
         </div>
       </div>