diff --git a/ArmPkg/Library/BaseMemoryLibStm/MemLibGuid.c b/ArmPkg/Library/BaseMemoryLibStm/MemLibGuid.c
index d4e504a013..1d90a8bca2 100755
--- a/ArmPkg/Library/BaseMemoryLibStm/MemLibGuid.c
+++ b/ArmPkg/Library/BaseMemoryLibStm/MemLibGuid.c
@@ -81,17 +81,7 @@ CompareGuid (
   IN CONST GUID  *Guid2
   )
 {
-  UINT64  LowPartOfGuid1;
-  UINT64  LowPartOfGuid2;
-  UINT64  HighPartOfGuid1;
-  UINT64  HighPartOfGuid2;
-
-  LowPartOfGuid1  = ReadUnaligned64 ((CONST UINT64*) Guid1);
-  LowPartOfGuid2  = ReadUnaligned64 ((CONST UINT64*) Guid2);
-  HighPartOfGuid1 = ReadUnaligned64 ((CONST UINT64*) Guid1 + 1);
-  HighPartOfGuid2 = ReadUnaligned64 ((CONST UINT64*) Guid2 + 1);
-
-  return (BOOLEAN) (LowPartOfGuid1 == LowPartOfGuid2 && HighPartOfGuid1 == HighPartOfGuid2);
+  return (CompareMem(Guid1, Guid2, sizeof(GUID)) == 0) ? TRUE : FALSE;
 }
 
 /**
diff --git a/ArmPkg/Library/BaseMemoryLibVstm/MemLibGuid.c b/ArmPkg/Library/BaseMemoryLibVstm/MemLibGuid.c
index d4e504a013..748c80eadd 100755
--- a/ArmPkg/Library/BaseMemoryLibVstm/MemLibGuid.c
+++ b/ArmPkg/Library/BaseMemoryLibVstm/MemLibGuid.c
@@ -81,17 +81,7 @@ CompareGuid (
   IN CONST GUID  *Guid2
   )
 {
-  UINT64  LowPartOfGuid1;
-  UINT64  LowPartOfGuid2;
-  UINT64  HighPartOfGuid1;
-  UINT64  HighPartOfGuid2;
-
-  LowPartOfGuid1  = ReadUnaligned64 ((CONST UINT64*) Guid1);
-  LowPartOfGuid2  = ReadUnaligned64 ((CONST UINT64*) Guid2);
-  HighPartOfGuid1 = ReadUnaligned64 ((CONST UINT64*) Guid1 + 1);
-  HighPartOfGuid2 = ReadUnaligned64 ((CONST UINT64*) Guid2 + 1);
-
-  return (BOOLEAN) (LowPartOfGuid1 == LowPartOfGuid2 && HighPartOfGuid1 == HighPartOfGuid2);
+  return (CompareMem(Guid1, Guid2, sizeof(GUID) == 0)) ? TRUE : FALSE;
 }
 
 /**