diff --git a/interfaces/kits/napi/file_access_module/root_info/napi_root_iterator_exporter.cpp b/interfaces/kits/napi/file_access_module/root_info/napi_root_iterator_exporter.cpp
index 0961321b52274278a287c15244e9737781429123..c840af4814e41e3dcf95ca7f90772ba891b2c90e 100644
--- a/interfaces/kits/napi/file_access_module/root_info/napi_root_iterator_exporter.cpp
+++ b/interfaces/kits/napi/file_access_module/root_info/napi_root_iterator_exporter.cpp
@@ -101,7 +101,7 @@ napi_value NapiRootIteratorExporter::Next(napi_env env, napi_callback_info info)
     bool done = true;
     {
         std::lock_guard<std::mutex> lock(rootIterator->entityOperateMutex);
-        auto len = (int64_t)rootIterator->devVec.size();
+        auto len = rootIterator->devVec.size();
         rootInfoEntity->fileAccessHelper = rootIterator->fileAccessHelper;
         if (rootIterator->pos < len) {
             rootInfoEntity->rootInfo = rootIterator->devVec[rootIterator->pos];
@@ -124,4 +124,4 @@ std::string NapiRootIteratorExporter::GetClassName()
     return NapiRootIteratorExporter::className_;
 }
 } // namespace FileAccessFwk
-} // namespace OHOS
\ No newline at end of file
+} // namespace OHOS