diff --git a/MdePkg/Include/Register/Intel/StmApi.h b/MdePkg/Include/Register/Intel/StmApi.h
index 9d42bcde76..6c1cdf988f 100644
--- a/MdePkg/Include/Register/Intel/StmApi.h
+++ b/MdePkg/Include/Register/Intel/StmApi.h
@@ -18,6 +18,8 @@
 
 #pragma pack (1)
 
+#define STM_SMM_REV_ID  0x80010100
+
 /**
   STM Header Structures
 **/