diff --git a/onnxruntime/core/flatbuffers/flatbuffers_utils.cc b/onnxruntime/core/flatbuffers/flatbuffers_utils.cc
index 06b5a7cceb9f2..1eb3bbdb1237f 100644
--- a/onnxruntime/core/flatbuffers/flatbuffers_utils.cc
+++ b/onnxruntime/core/flatbuffers/flatbuffers_utils.cc
@@ -163,8 +163,9 @@ Status SaveValueInfoOrtFormat(flatbuffers::FlatBufferBuilder& builder,
 #endif  // #if !defined(ORT_MINIMAL_BUILD)
 
 void LoadStringFromOrtFormat(std::string& dst, const flatbuffers::String* fbs_string) {
-  if (fbs_string)
-    dst = fbs_string->c_str();
+  if (fbs_string) {
+    dst = fbs_string->str();
+  }
 }
 
 static Status LoadTypeInfoOrtFormat(const fbs::TypeInfo& fbs_type_info,
diff --git a/onnxruntime/core/flatbuffers/flatbuffers_utils.h b/onnxruntime/core/flatbuffers/flatbuffers_utils.h
index 76860d6ab1db8..aed0c201a2dd5 100644
--- a/onnxruntime/core/flatbuffers/flatbuffers_utils.h
+++ b/onnxruntime/core/flatbuffers/flatbuffers_utils.h
@@ -40,7 +40,7 @@ void LoadStringFromOrtFormat(std::string& dst, const flatbuffers::String* fbs_st
 #define LOAD_STR_FROM_ORT_FORMAT(protobuf_msg, str_field, fbs_string) \
   {                                                                   \
     if (fbs_string)                                                   \
-      protobuf_msg.set_##str_field(fbs_string->c_str());              \
+      protobuf_msg.set_##str_field(fbs_string->str());                \
   }
 
 onnxruntime::common::Status LoadValueInfoOrtFormat(