diff --git a/MdePkg/Include/IndustryStandard/Atapi.h b/MdePkg/Include/IndustryStandard/Atapi.h
index 1c18441858..f14d8f25c4 100644
--- a/MdePkg/Include/IndustryStandard/Atapi.h
+++ b/MdePkg/Include/IndustryStandard/Atapi.h
@@ -484,7 +484,6 @@ typedef union {
 //
 // Sense Key
 //
-#define ATA_REQUEST_SENSE_ERROR (0x70)
 #define ATA_SK_NO_SENSE         (0x0)
 #define ATA_SK_RECOVERY_ERROR   (0x1)
 #define ATA_SK_NOT_READY        (0x2)