diff --git a/backend/apps/chat/api/chat.py b/backend/apps/chat/api/chat.py
index ed632f3a..e1f1d4dc 100644
--- a/backend/apps/chat/api/chat.py
+++ b/backend/apps/chat/api/chat.py
@@ -1,4 +1,5 @@
 import json
+import orjson
 import traceback
 from typing import List
 
@@ -138,7 +139,7 @@ async def stream_sql(session: SessionDep, current_user: CurrentUser, request_que
             # execute sql
             result = llm_service.execute_sql(sql=sql)
             llm_service.save_sql_data(session=session, data_obj=result)
-            yield json.dumps({'content': json.dumps(result, ensure_ascii=False), 'type': 'sql-data'}) + '\n\n'
+            yield json.dumps({'content': orjson.dumps(result).decode(), 'type': 'sql-data'}) + '\n\n'
 
             # generate chart
             chart_res = llm_service.generate_chart(session=session)
diff --git a/backend/apps/chat/task/llm.py b/backend/apps/chat/task/llm.py
index dee73241..c6fa330d 100644
--- a/backend/apps/chat/task/llm.py
+++ b/backend/apps/chat/task/llm.py
@@ -1,4 +1,5 @@
 import json
+import orjson
 import logging
 import warnings
 from typing import Any, List, Union, Dict
@@ -218,7 +219,7 @@ class LLMService:
 
     def save_sql_data(self, session: SessionDep, data_obj: Dict[str, Any]):
         return save_sql_exec_data(session=session, record_id=self.record.id,
-                                  data=json.dumps(data_obj, ensure_ascii=False))
+                                  data=orjson.dumps(data_obj).decode())
 
     def finish(self, session: SessionDep):
         return finish_record(session=session, record_id=self.record.id)