diff --git a/pilot/scene/chat_db/professional_qa/chat.py b/pilot/scene/chat_db/professional_qa/chat.py
index faffcc146..cb2425ea9 100644
--- a/pilot/scene/chat_db/professional_qa/chat.py
+++ b/pilot/scene/chat_db/professional_qa/chat.py
@@ -35,7 +35,13 @@ class ChatWithDbQA(BaseChat):
             self.database = CFG.local_db
             # 准备DB信息(拿到指定库的链接)
             self.db_connect = self.database.get_session(self.db_name)
-        self.top_k: int = 5
+            self.tables = self.database.get_table_names()
+
+        self.top_k = (
+            CFG.KNOWLEDGE_SEARCH_TOP_SIZE
+            if len(self.tables) > CFG.KNOWLEDGE_SEARCH_TOP_SIZE
+            else len(self.tables)
+        )
 
     def generate_input_values(self):
         table_info = ""