diff --git a/src/client/src/tscSql.c b/src/client/src/tscSql.c
index a0089379a9c71434ed1a7aa7547724145241b89f..210c63adb6c97fd9bf9d7399e79feb04ac7a0de9 100644
--- a/src/client/src/tscSql.c
+++ b/src/client/src/tscSql.c
@@ -321,6 +321,9 @@ TAOS_FIELD *taos_fetch_fields(TAOS_RES *res) {
   if (pSql == NULL || pSql->signature != pSql) return 0;
 
   SQueryInfo *pQueryInfo = tscGetQueryInfoDetail(&pSql->cmd, 0);
+  if(NULL == pQueryInfo){
+    return NULL;
+  }
   return pQueryInfo->fieldsInfo.pFields;
 }