diff --git a/src/main/ipc.ts b/src/main/ipc.ts
index e6b3b4a..2ca4386 100644
--- a/src/main/ipc.ts
+++ b/src/main/ipc.ts
@@ -262,10 +262,10 @@ export async function setupIPC(): Promise<void> {
   });
 
   ipcMain.handle('tool:setTimeouts', (_, timeouts: { http?: number; mcp?: number }) => {
-    if (typeof timeouts.http === 'number' && timeouts.http > 0) {
+    if (typeof timeouts.http === 'number' && timeouts.http >= 0) {
       setHTTPTimeout(timeouts.http);
     }
-    if (typeof timeouts.mcp === 'number' && timeouts.mcp > 0) {
+    if (typeof timeouts.mcp === 'number' && timeouts.mcp >= 0) {
       setMCPTimeout(timeouts.mcp);
     }
     return { success: true };
diff --git a/src/main/mcp-manager.ts b/src/main/mcp-manager.ts
index c0cc884..3423a87 100644
--- a/src/main/mcp-manager.ts
+++ b/src/main/mcp-manager.ts
@@ -42,7 +42,7 @@ interface MCPServerInstance {
   config: { name: string; command: string; args: string[]; enabled: boolean; description?: string };
   process: ChildProcess;
   requestId: number;
-  pendingRequests: Map<number, { resolve: (value: unknown) => void; reject: (reason: Error) => void; timer: ReturnType<typeof setTimeout> }>;
+  pendingRequests: Map<number, { resolve: (value: unknown) => void; reject: (reason: Error) => void; timer: ReturnType<typeof setTimeout> | null }>;
   buffer: string;
   tools: MCPTool[];
   initialized: boolean;
@@ -55,9 +55,9 @@ const servers = new Map<string, MCPServerInstance>();
 /** MCP 请求超时（毫秒），默认 60s，可通过 IPC 设置 */
 let MCP_TIMEOUT = 60_000;
 
-/** 设置 MCP 请求超时（毫秒） */
+/** 设置 MCP 请求超时（毫秒），0=禁用超时 */
 export function setMCPTimeout(ms: number): void {
-  MCP_TIMEOUT = Math.max(10_000, ms);
+  MCP_TIMEOUT = ms === 0 ? 0 : Math.max(10_000, ms);
 }
 
 // ─── JSON-RPC 通信 ───
@@ -67,10 +67,10 @@ function sendRequest(server: MCPServerInstance, method: string, params?: Record<
     const id = ++server.requestId;
     const request: JSONRPCRequest = { jsonrpc: '2.0', id, method, params };
 
-    const timer = setTimeout(() => {
+    const timer = MCP_TIMEOUT > 0 ? setTimeout(() => {
       server.pendingRequests.delete(id);
       reject(new Error(`MCP 请求超时: ${server.config.name} / ${method} (${MCP_TIMEOUT}ms)`));
-    }, MCP_TIMEOUT);
+    }, MCP_TIMEOUT) : null;
 
     server.pendingRequests.set(id, { resolve, reject, timer });
 
@@ -79,7 +79,7 @@ function sendRequest(server: MCPServerInstance, method: string, params?: Record<
       server.process.stdin!.write(line);
     } catch (err) {
       server.pendingRequests.delete(id);
-      clearTimeout(timer);
+      if (timer) clearTimeout(timer);
       reject(new Error(`MCP 写入失败: ${(err as Error).message}`));
     }
   });
@@ -89,7 +89,7 @@ function handleResponse(server: MCPServerInstance, response: JSONRPCResponse): v
   const pending = server.pendingRequests.get(response.id);
   if (!pending) return;
 
-  clearTimeout(pending.timer);
+  if (pending.timer) clearTimeout(pending.timer);
   server.pendingRequests.delete(response.id);
 
   if (response.error) {
@@ -201,7 +201,7 @@ export async function startServer(config: { name: string; command: string; args:
 
 function cleanupServer(server: MCPServerInstance): void {
   for (const [, pending] of server.pendingRequests) {
-    clearTimeout(pending.timer);
+    if (pending.timer) clearTimeout(pending.timer);
     pending.reject(new Error('MCP 服务器已关闭'));
   }
   server.pendingRequests.clear();
diff --git a/src/main/tool-handlers-system.ts b/src/main/tool-handlers-system.ts
index 736647e..caed0f2 100644
--- a/src/main/tool-handlers-system.ts
+++ b/src/main/tool-handlers-system.ts
@@ -127,9 +127,9 @@ export function killToolProcess(): boolean {
 /** HTTP 请求超时（毫秒），默认 30s，可通过 IPC 设置 */
 let HTTP_TIMEOUT = 30_000;
 
-/** 设置 HTTP 请求超时（毫秒） */
+/** 设置 HTTP 请求超时（毫秒），0=禁用超时 */
 export function setHTTPTimeout(ms: number): void {
-  HTTP_TIMEOUT = Math.max(5000, ms);
+  HTTP_TIMEOUT = ms === 0 ? 0 : Math.max(5000, ms);
 }
 
 // ── LRU 搜索缓存 ──────────────────────────────────
@@ -233,10 +233,17 @@ function buildFetchHeaders(url: string, attemptIndex: number, useMobileUA: boole
   };
 }
 
-/** 带超时的 fetch 封装 */
+/** 带超时的 fetch 封装，timeout=0 表示不超时 */
 async function fetchWithTimeout(url: string, timeout = HTTP_TIMEOUT, headers?: Record<string,string>, attemptIndex = 0): Promise<Response | null> {
   const _headers = headers || buildFetchHeaders(url, attemptIndex);
 
+  if (timeout <= 0) {
+    // 0 = 禁用超时
+    try {
+      return await fetch(url, { headers: _headers, redirect: 'follow' });
+    } catch { return null; }
+  }
+
   const controller = new AbortController();
   const tid = setTimeout(() => controller.abort(), timeout);
   try {
@@ -444,13 +451,18 @@ export async function handleWebFetch(params: { url: string; max_chars?: number;
     const headers = buildFetchHeaders(url, attempt, useMobileUA);
 
     try {
-      const controller = new AbortController();
-      const timeoutId = setTimeout(() => controller.abort(), HTTP_TIMEOUT);
       let resp: Response;
-      try {
-        resp = await fetch(url, { headers, signal: controller.signal, redirect: 'follow' });
-      } finally {
-        clearTimeout(timeoutId);
+      if (HTTP_TIMEOUT > 0) {
+        const controller = new AbortController();
+        const timeoutId = setTimeout(() => controller.abort(), HTTP_TIMEOUT);
+        try {
+          resp = await fetch(url, { headers, signal: controller.signal, redirect: 'follow' });
+        } finally {
+          clearTimeout(timeoutId);
+        }
+      } else {
+        // 0 = 禁用超时
+        resp = await fetch(url, { headers, redirect: 'follow' });
       }
 
       if (!resp.ok) {
@@ -566,7 +578,7 @@ export async function handleWebFetch(params: { url: string; max_chars?: number;
     } catch (err) {
       const errMsg = (err as Error).message;
       if (errMsg.includes('abort') && attempt < maxAttempts - 1) {
-        lastError = `请求超时 (${HTTP_TIMEOUT / 1000}s)（将重试）`;
+        lastError = `请求超时 (${HTTP_TIMEOUT > 0 ? HTTP_TIMEOUT / 1000 : '∞'}s)（将重试）`;
         continue;
       }
       if (errMsg.includes('abort')) {
diff --git a/src/renderer/services/agent-engine.ts b/src/renderer/services/agent-engine.ts
index ceeed21..80d3de7 100644
--- a/src/renderer/services/agent-engine.ts
+++ b/src/renderer/services/agent-engine.ts
@@ -1336,12 +1336,21 @@ async function handleThinking(
 
 	  const abortController = registerAbortController();
 
-  // ── 流式超时保护 — 动态计算：基础 120s + 上下文 token 数 * 0.5s/1K tokens ──
+  // ── 流式超时保护 — 0=禁用, 正数=自定义, -1/未设置=动态计算 ──
   const baseTimeout = state.get<number>('streamTimeout', 0);
   const numCtxForTimeout = getEffectiveNumCtx();
-  const dynamicTimeout = baseTimeout > 0 ? baseTimeout : Math.max(120_000, 120_000 + Math.floor(numCtxForTimeout / 1000) * 500);
-  // 上限 10 分钟，避免极端值
-  const STREAM_TIMEOUT_MS = Math.min(dynamicTimeout, 600_000);
+  let STREAM_TIMEOUT_MS: number;
+  if (baseTimeout === 0) {
+    // 0 = 禁用流式超时
+    STREAM_TIMEOUT_MS = 0;
+  } else if (baseTimeout > 0) {
+    // 用户自定义超时，上限 10 分钟
+    STREAM_TIMEOUT_MS = Math.min(baseTimeout, 600_000);
+  } else {
+    // -1 或未设置 = 动态计算：基础 120s + 上下文 token 数 * 0.5s/1K tokens
+    const dynamicTimeout = Math.max(120_000, 120_000 + Math.floor(numCtxForTimeout / 1000) * 500);
+    STREAM_TIMEOUT_MS = Math.min(dynamicTimeout, 600_000);
+  }
 
   let totalTimer: ReturnType<typeof setTimeout> | null = null;