diff --git a/components/SmartChatBox/useMessages.ts b/components/SmartChatBox/useMessages.ts
index e0068f3..cbc4760 100644
--- a/components/SmartChatBox/useMessages.ts
+++ b/components/SmartChatBox/useMessages.ts
@@ -30,6 +30,21 @@ export function useMessages({ config, onMessagesUpdate }: UseMessagesProps): [Me
   const timeoutIdRef = useRef<NodeJS.Timeout | null>(null);
   const isViewingHistoryRef = useRef(false);
   const prevTotalCountRef = useRef(totalCount);
+  const isPollingRef = useRef(false);
+
+  // 合并和去重消息
+  const mergeMessages = useCallback((oldMessages: ChatMessage[], newMessages: ChatMessage[]) => {
+    const messageMap = new Map<string, ChatMessage>();
+    
+    // 使用 Map 自动去重，后面的会覆盖前面的
+    [...oldMessages, ...newMessages].forEach(msg => {
+      messageMap.set(msg.id, msg);
+    });
+
+    // 转回数组并按 id 排序
+    return Array.from(messageMap.values())
+      .sort((a, b) => Number(a.id) - Number(b.id));
+  }, []);
 
   // 更新 config 引用
   useEffect(() => {
@@ -46,7 +61,7 @@ export function useMessages({ config, onMessagesUpdate }: UseMessagesProps): [Me
   }, [totalCount, onMessagesUpdate]);
 
   // 获取最新消息
-  const fetchLatestMessages = useCallback(async (showLoading: boolean = false) => {
+  const updateMessages = useCallback(async (showLoading: boolean = false) => {
     try {
       if (showLoading) {
         setIsLoading(true);
@@ -79,7 +94,9 @@ export function useMessages({ config, onMessagesUpdate }: UseMessagesProps): [Me
       setIsLoading(true);
       
       const response = await fetchMessages(configRef.current, offset, PAGE_SIZE);
-      setDisplayMessages(prev => [...response.messages, ...prev]);
+      
+      // 合并并去重消息
+      setDisplayMessages(prev => mergeMessages(prev, response.messages));
       setHasMore(response.hasMore);
       setOffset(prev => prev + PAGE_SIZE);
       setTotalCount(response.totalCount);
@@ -89,7 +106,7 @@ export function useMessages({ config, onMessagesUpdate }: UseMessagesProps): [Me
     } finally {
       setIsLoading(false);
     }
-  }, [offset, hasMore, isLoading]);
+  }, [offset, hasMore, isLoading, mergeMessages]);
 
   // 返回最新消息
   const backToLatest = useCallback(async () => {
@@ -116,20 +133,20 @@ export function useMessages({ config, onMessagesUpdate }: UseMessagesProps): [Me
 
       // 无论是否在查看历史，发送消息后都切换到最新视图
       isViewingHistoryRef.current = false;
-      setDisplayMessages(prev => [...prev, userMessage]);
+      setDisplayMessages(prev => mergeMessages(prev, [userMessage]));
 
       // 发送到服务器
       await sendMessage(blocks, configRef.current);
       
       // 立即获取最新的消息列表
-      await fetchLatestMessages(false);
+      await updateMessages(false);
     } catch (err) {
       console.error("发送消息失败:", err);
       setError(err instanceof Error ? err : new Error("发送消息失败"));
     } finally {
       setIsLoading(false);
     }
-  }, [fetchLatestMessages]);
+  }, [updateMessages, mergeMessages]);
 
   // 重试消息
   const handleRetryMessage = useCallback(async (messageId: string) => {
@@ -140,14 +157,14 @@ export function useMessages({ config, onMessagesUpdate }: UseMessagesProps): [Me
       // 重试时切换到最新视图
       isViewingHistoryRef.current = false;
       await retryMessage(messageId, configRef.current);
-      await fetchLatestMessages(false);
+      await updateMessages(false);
     } catch (err) {
       console.error("重试消息失败:", err);
       setError(err instanceof Error ? err : new Error("重试消息失败"));
     } finally {
       setIsLoading(false);
     }
-  }, [fetchLatestMessages]);
+  }, [updateMessages]);
 
   // 清空消息
   const handleClearMessages = useCallback(() => {
@@ -168,8 +185,17 @@ export function useMessages({ config, onMessagesUpdate }: UseMessagesProps): [Me
     if (!systemPush) return;
 
     const poll = async () => {
-      await fetchLatestMessages(false);
-      timeoutIdRef.current = setTimeout(poll, POLLING_INTERVAL);
+      if (isPollingRef.current) return;
+      
+      try {
+        isPollingRef.current = true;
+        await updateMessages(false);
+      } finally {
+        isPollingRef.current = false;
+        if (systemPush) {
+          timeoutIdRef.current = setTimeout(poll, POLLING_INTERVAL);
+        }
+      }
     };
 
     poll();
@@ -179,15 +205,15 @@ export function useMessages({ config, onMessagesUpdate }: UseMessagesProps): [Me
         clearTimeout(timeoutIdRef.current);
       }
     };
-  }, [systemPush, fetchLatestMessages]);
+  }, [systemPush, updateMessages]);
 
   // 初始加载
   useEffect(() => {
     if (isInitialLoadRef.current) {
       isInitialLoadRef.current = false;
-      fetchLatestMessages(true);
+      updateMessages(true);
     }
-  }, [fetchLatestMessages]);
+  }, [updateMessages]);
 
   return [
     {