diff --git a/MdePkg/Library/BaseLib/BaseLib.inf b/MdePkg/Library/BaseLib/BaseLib.inf
index f3a6a6b61d..35ca89b284 100644
--- a/MdePkg/Library/BaseLib/BaseLib.inf
+++ b/MdePkg/Library/BaseLib/BaseLib.inf
@@ -533,6 +533,7 @@
   X64/ReadEs.asm | MSFT
   X64/ReadDs.nasm| MSFT
   X64/ReadDs.asm | MSFT
+  X64/ReadCs.nasm| MSFT
   X64/ReadCs.asm | MSFT
   X64/WriteDr7.asm | MSFT
   X64/WriteDr6.asm | MSFT
@@ -649,6 +650,7 @@
   X64/ReadEs.asm | INTEL
   X64/ReadDs.nasm| INTEL
   X64/ReadDs.asm | INTEL
+  X64/ReadCs.nasm| INTEL
   X64/ReadCs.asm | INTEL
   X64/WriteDr7.asm | INTEL
   X64/WriteDr6.asm | INTEL
diff --git a/MdePkg/Library/BaseLib/X64/ReadCs.nasm b/MdePkg/Library/BaseLib/X64/ReadCs.nasm
new file mode 100644
index 0000000000..88e3a601e2
--- /dev/null
+++ b/MdePkg/Library/BaseLib/X64/ReadCs.nasm
@@ -0,0 +1,38 @@
+;------------------------------------------------------------------------------
+;
+; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>
+; This program and the accompanying materials
+; are licensed and made available under the terms and conditions of the BSD License
+; which accompanies this distribution.  The full text of the license may be found at
+; http://opensource.org/licenses/bsd-license.php.
+;
+; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+;
+; Module Name:
+;
+;   ReadCs.Asm
+;
+; Abstract:
+;
+;   AsmReadCs function
+;
+; Notes:
+;
+;------------------------------------------------------------------------------
+
+    DEFAULT REL
+    SECTION .text
+
+;------------------------------------------------------------------------------
+; UINT16
+; EFIAPI
+; AsmReadCs (
+;   VOID
+;   );
+;------------------------------------------------------------------------------
+global ASM_PFX(AsmReadCs)
+ASM_PFX(AsmReadCs):
+    mov     eax, cs
+    ret
+