diff --git a/OvmfPkg/Include/IndustryStandard/IntelTdx.h b/OvmfPkg/Include/IndustryStandard/IntelTdx.h
new file mode 100644
index 0000000000..cc849be2fb
--- /dev/null
+++ b/OvmfPkg/Include/IndustryStandard/IntelTdx.h
@@ -0,0 +1,67 @@
+/** @file
+  Defines the defitions used by TDX in OvmfPkg.
+
+  Copyright (c) 2020 - 2021, Intel Corporation. All rights reserved.<BR>
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef OVMF_INTEL_TDX_H_
+#define OVMF_INTEL_TDX_H_
+
+#include <PiPei.h>
+#include <Library/BaseLib.h>
+#include <Uefi/UefiSpec.h>
+#include <Uefi/UefiBaseType.h>
+
+#define MP_CPU_PROTECTED_MODE_MAILBOX_APICID_INVALID    0xFFFFFFFF
+#define MP_CPU_PROTECTED_MODE_MAILBOX_APICID_BROADCAST  0xFFFFFFFE
+
+typedef enum {
+  MpProtectedModeWakeupCommandNoop        = 0,
+  MpProtectedModeWakeupCommandWakeup      = 1,
+  MpProtectedModeWakeupCommandSleep       = 2,
+  MpProtectedModeWakeupCommandAcceptPages = 3,
+} MP_CPU_PROTECTED_MODE_WAKEUP_CMD;
+
+#pragma pack(1)
+
+//
+// Describes the CPU MAILBOX control structure use to
+// wakeup cpus spinning in long mode
+//
+typedef struct {
+  UINT16    Command;
+  UINT16    Resv;
+  UINT32    ApicId;
+  UINT64    WakeUpVector;
+  UINT8     ResvForOs[2032];
+  //
+  // Arguments available for wakeup code
+  //
+  UINT64    WakeUpArgs1;
+  UINT64    WakeUpArgs2;
+  UINT64    WakeUpArgs3;
+  UINT64    WakeUpArgs4;
+  UINT8     Pad1[0xe0];
+  UINT64    NumCpusArriving;
+  UINT8     Pad2[0xf8];
+  UINT64    NumCpusExiting;
+  UINT32    Tallies[256];
+  UINT8     Errors[256];
+  UINT8     Pad3[0xf8];
+} MP_WAKEUP_MAILBOX;
+
+//
+// AP relocation code information including code address and size,
+// this structure will be shared be C code and assembly code.
+// It is natural aligned by design.
+//
+typedef struct {
+  UINT8    *RelocateApLoopFuncAddress;
+  UINTN    RelocateApLoopFuncSize;
+} MP_RELOCATION_MAP;
+
+#pragma pack()
+
+#endif