diff --git a/include/onnxruntime/core/session/onnxruntime_c_api.h b/include/onnxruntime/core/session/onnxruntime_c_api.h
index b6c51baa90..49b924f0a6 100644
--- a/include/onnxruntime/core/session/onnxruntime_c_api.h
+++ b/include/onnxruntime/core/session/onnxruntime_c_api.h
@@ -373,7 +373,8 @@ typedef enum OrtAllocatorType {
 } OrtAllocatorType;
 
 /**
-   memory types for allocator, exec provider specific types should be extended in each provider
+ * memory types for allocator, exec provider specific types should be extended in each provider
+ * Whenever this struct is updated, please also update the MakeKey function in onnxruntime/core/framework/execution_provider.cc
 */
 typedef enum OrtMemType {
   OrtMemTypeCPUInput = -2,              // Any CPU memory used by non-CPU execution provider
diff --git a/onnxruntime/core/framework/execution_provider.cc b/onnxruntime/core/framework/execution_provider.cc
index b3be350c2c..a0bd30bae1 100644
--- a/onnxruntime/core/framework/execution_provider.cc
+++ b/onnxruntime/core/framework/execution_provider.cc
@@ -11,8 +11,9 @@
 namespace onnxruntime {
 
 namespace {
+//It assumes max(OrtMemType) <= 1, min(OrtMemType) = -2
 inline int MakeKey(int id, OrtMemType mem_type) {
-  return id << 2 | mem_type;
+  return id << 2 | (mem_type + 2);
 }
 }  // namespace