diff --git a/MdePkg/Include/IndustryStandard/Tpm20.h b/MdePkg/Include/IndustryStandard/Tpm20.h
index 2abfc57df8..0505927010 100644
--- a/MdePkg/Include/IndustryStandard/Tpm20.h
+++ b/MdePkg/Include/IndustryStandard/Tpm20.h
@@ -147,7 +147,6 @@ typedef UINT64                        CONTEXT_COUNTER;
 
 // Table 3 - Definition of Base Types
 typedef UINT8 BYTE;
-typedef UINT8 BOOL;
 
 // Table 4 - Definition of Types for Documentation Clarity
 //