diff --git a/StandaloneMmPkg/Include/Library/FvLib.h b/StandaloneMmPkg/Include/Library/FvLib.h
index c08e043cf6..4ef2c8540a 100644
--- a/StandaloneMmPkg/Include/Library/FvLib.h
+++ b/StandaloneMmPkg/Include/Library/FvLib.h
@@ -50,6 +50,7 @@ FfsFindNextFile (
   @retval  EFI_SUCCESS
 **/
 EFI_STATUS
+EFIAPI
 FfsFindSection (
   IN EFI_SECTION_TYPE              SectionType,
   IN EFI_FFS_FILE_HEADER           *FfsFileHeader,