diff --git a/EdkCompatibilityPkg/Foundation/Include/EfiVariable.h b/EdkCompatibilityPkg/Foundation/Include/EfiVariable.h
index b2a96f4a48..a463cac75a 100644
--- a/EdkCompatibilityPkg/Foundation/Include/EfiVariable.h
+++ b/EdkCompatibilityPkg/Foundation/Include/EfiVariable.h
@@ -24,14 +24,18 @@ Abstract:
 
 #define VARIABLE_STORE_SIGNATURE  EFI_SIGNATURE_32 ('$', 'V', 'S', 'S')
 
+#ifndef MAX_VARIABLE_SIZE
 #define MAX_VARIABLE_SIZE         1024
+#endif
 
 //
 // Enlarges the hardware error record maximum variable size to 32K bytes
 //
 #if (EFI_SPECIFICATION_VERSION >= 0x0002000A)
+#ifndef MAX_HARDWARE_ERROR_VARIABLE_SIZE
 #define MAX_HARDWARE_ERROR_VARIABLE_SIZE 0x8000
 #endif
+#endif
 
 #define VARIABLE_DATA             0x55AA