diff --git a/api/core/ops/aliyun_trace/aliyun_trace.py b/api/core/ops/aliyun_trace/aliyun_trace.py
index 1b2445ddaa..163b5d0307 100644
--- a/api/core/ops/aliyun_trace/aliyun_trace.py
+++ b/api/core/ops/aliyun_trace/aliyun_trace.py
@@ -346,7 +346,7 @@ class AliyunDataTrace(BaseTraceInstance):
         input_value = ""
         if node_execution.inputs:
             input_value = str(node_execution.inputs.get("query", ""))
-        output_value = []
+        output_value = ""
         if node_execution.outputs:
             output_value = json.dumps(node_execution.outputs.get("result", []), ensure_ascii=False)
         return SpanData(