diff --git a/UefiCpuPkg/Library/MpInitLib/Ia32/MpFuncs.nasm b/UefiCpuPkg/Library/MpInitLib/Ia32/MpFuncs.nasm
index 4363ad9a18..7bd2415670 100644
--- a/UefiCpuPkg/Library/MpInitLib/Ia32/MpFuncs.nasm
+++ b/UefiCpuPkg/Library/MpInitLib/Ia32/MpFuncs.nasm
@@ -121,10 +121,6 @@ SkipEnableExecuteDisable:
     lock inc   dword [edi]
 
     ; AP init
-    mov        edi, esi
-    add        edi, MP_CPU_EXCHANGE_INFO_FIELD (Lock)
-    mov        eax, NotVacantFlag
-
     mov        edi, esi
     add        edi, MP_CPU_EXCHANGE_INFO_FIELD (ApIndex)
     mov        ebx, 1
diff --git a/UefiCpuPkg/Library/MpInitLib/MpEqu.inc b/UefiCpuPkg/Library/MpInitLib/MpEqu.inc
index 46c2b5c116..2e9368a374 100644
--- a/UefiCpuPkg/Library/MpInitLib/MpEqu.inc
+++ b/UefiCpuPkg/Library/MpInitLib/MpEqu.inc
@@ -13,9 +13,6 @@
 ;-------------------------------------------------------------------------------
 %include "Nasm.inc"
 
-VacantFlag                    equ        00h
-NotVacantFlag                 equ        0ffh
-
 CPU_SWITCH_STATE_IDLE         equ        0
 CPU_SWITCH_STATE_STORED       equ        1
 CPU_SWITCH_STATE_LOADED       equ        2
@@ -72,7 +69,6 @@ endstruc
 ; Equivalent NASM structure of MP_CPU_EXCHANGE_INFO
 ;
 struc MP_CPU_EXCHANGE_INFO
-  .Lock:                         CTYPE_UINTN 1
   .StackStart:                   CTYPE_UINTN 1
   .StackSize:                    CTYPE_UINTN 1
   .CFunction:                    CTYPE_UINTN 1
diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.c b/UefiCpuPkg/Library/MpInitLib/MpLib.c
index 2568986d8c..5040053dad 100644
--- a/UefiCpuPkg/Library/MpInitLib/MpLib.c
+++ b/UefiCpuPkg/Library/MpInitLib/MpLib.c
@@ -1006,7 +1006,6 @@ FillExchangeInfoData (
   IA32_CR4                         Cr4;
 
   ExchangeInfo                  = CpuMpData->MpCpuExchangeInfo;
-  ExchangeInfo->Lock            = 0;
   ExchangeInfo->StackStart      = CpuMpData->Buffer;
   ExchangeInfo->StackSize       = CpuMpData->CpuApStackSize;
   ExchangeInfo->BufferStart     = CpuMpData->WakeupBuffer;
diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.h b/UefiCpuPkg/Library/MpInitLib/MpLib.h
index 02652eaae1..0bd60388b1 100644
--- a/UefiCpuPkg/Library/MpInitLib/MpLib.h
+++ b/UefiCpuPkg/Library/MpInitLib/MpLib.h
@@ -1,7 +1,7 @@
 /** @file
   Common header file for MP Initialize Library.
 
-  Copyright (c) 2016 - 2020, Intel Corporation. All rights reserved.<BR>
+  Copyright (c) 2016 - 2021, Intel Corporation. All rights reserved.<BR>
   Copyright (c) 2020, AMD Inc. All rights reserved.<BR>
 
   SPDX-License-Identifier: BSD-2-Clause-Patent
@@ -190,7 +190,6 @@ typedef struct _CPU_MP_DATA  CPU_MP_DATA;
 // into this structure are used in assembly code in this module
 //
 typedef struct {
-  UINTN                 Lock;
   UINTN                 StackStart;
   UINTN                 StackSize;
   UINTN                 CFunction;
diff --git a/UefiCpuPkg/Library/MpInitLib/X64/MpFuncs.nasm b/UefiCpuPkg/Library/MpInitLib/X64/MpFuncs.nasm
index db297f5cca..50df802d1f 100644
--- a/UefiCpuPkg/Library/MpInitLib/X64/MpFuncs.nasm
+++ b/UefiCpuPkg/Library/MpInitLib/X64/MpFuncs.nasm
@@ -157,10 +157,6 @@ LongModeStart:
     lock inc   dword [edi]
 
     ; AP init
-    mov        edi, esi
-    add        edi, MP_CPU_EXCHANGE_INFO_FIELD (Lock)
-    mov        rax, NotVacantFlag
-
     mov        edi, esi
     add        edi, MP_CPU_EXCHANGE_INFO_FIELD (ApIndex)
     mov        ebx, 1