diff --git a/source/libs/stream/src/streamDispatch.c b/source/libs/stream/src/streamDispatch.c
index 922a1f534592dd11a1af7f34592a8251f178ec7b..7af3219f85f16bc0e87af16e66b2ef576ae2951c 100644
--- a/source/libs/stream/src/streamDispatch.c
+++ b/source/libs/stream/src/streamDispatch.c
@@ -349,6 +349,7 @@ int32_t streamSearchAndAddBlock(SStreamTask* pTask, SStreamDispatchReq* pReqs, S
     SBlockName* pBln = (SBlockName*)pVal;
     hashValue = pBln->hashValue;
     if (!pDataBlock->info.parTbName[0]) {
+      memset(pDataBlock->info.parTbName, 0, TSDB_TABLE_NAME_LEN);
       memcpy(pDataBlock->info.parTbName, pBln->parTbName, strlen(pBln->parTbName));
     }
   } else {