diff --git a/interfaces/kits/napi/common/napi_parse_utils.cpp b/interfaces/kits/napi/common/napi_parse_utils.cpp
index 3dda38d7096b93c608c7ef79c8b16f7153485e01..8030abb3a3d8cdb2ec2c4a12069c5e546a016b0c 100644
--- a/interfaces/kits/napi/common/napi_parse_utils.cpp
+++ b/interfaces/kits/napi/common/napi_parse_utils.cpp
@@ -509,7 +509,8 @@ ErrCode NapiParseUtils::ConstructArrayBufFlowbuf(napi_env env, napi_value argv,
     }
 
     // write to ashmem
-    memcpy_s(ashmem, scriptLength + 1, arrBuf, scriptLength + 1);
+    memcpy_s(ashmem, scriptLength + 1, arrBuf, scriptLength);
+    static_cast<char*>(ashmem)[scriptLength] = '\0';
     return NWebError::NO_ERROR;
 }
 } // namespace NWeb