diff --git a/source/client/src/clientSml.c b/source/client/src/clientSml.c
index 1cb0e2d54b..5039f8bbaf 100644
--- a/source/client/src/clientSml.c
+++ b/source/client/src/clientSml.c
@@ -2456,10 +2456,10 @@ TAOS_RES* taos_schemaless_insert(TAOS* taos, char* lines[], int numLines, int pr
     return NULL;
   }
 
+  int    batchs = 0;
   pTscObj->schemalessType = 1;
   SSmlMsgBuf msg = {ERROR_MSG_BUF_DEFAULT_SIZE, request->msgBuf};
 
-  int    cnt = ceil(((double)numLines) / LINE_BATCH);
   Params params;
   params.request = request;
   tsem_init(&params.sem, 0, 0);
@@ -2496,7 +2496,16 @@ TAOS_RES* taos_schemaless_insert(TAOS* taos, char* lines[], int numLines, int pr
     goto end;
   }
 
-  for (int i = 0; i < cnt; ++i) {
+  if(protocol == TSDB_SML_JSON_PROTOCOL){
+    numLines = 1;
+  }else if(numLines <= 0){
+    request->code = TSDB_CODE_SML_INVALID_DATA;
+    smlBuildInvalidDataMsg(&msg, "line num is invalid", NULL);
+    goto end;
+  }
+
+  batchs = ceil(((double)numLines) / LINE_BATCH);
+  for (int i = 0; i < batchs; ++i) {
     SRequestObj* req = (SRequestObj*)createRequest(pTscObj, TSDB_SQL_INSERT);
     if(!req){
       request->code = TSDB_CODE_OUT_OF_MEMORY;