diff --git a/MdePkg/Include/Guid/FirmwareFileSystem2.h b/MdePkg/Include/Guid/FirmwareFileSystem2.h
index 9dbee75cfe..4a3adbb03d 100644
--- a/MdePkg/Include/Guid/FirmwareFileSystem2.h
+++ b/MdePkg/Include/Guid/FirmwareFileSystem2.h
@@ -34,7 +34,7 @@
   { 0x1BA0062E, 0xC779, 0x4582, { 0x85, 0x66, 0x33, 0x6A, 0xE8, 0xF7, 0x8F, 0x9 } }
 
 
-extern EFI_GUID gEfiFirmwareFileSystemGuid;
+extern EFI_GUID gEfiFirmwareFileSystem2Guid;
 extern EFI_GUID gEfiFirmwareVolumeTopFileGuid;
 
 #endif