diff --git a/MdePkg/MdePkg.dec b/MdePkg/MdePkg.dec
index 6b4e73f7cb..d25eabed5b 100644
--- a/MdePkg/MdePkg.dec
+++ b/MdePkg/MdePkg.dec
@@ -496,6 +496,7 @@
   gEfiMdePkgTokenSpaceGuid.PcdUartDefaultParity|1|UINT8|0x00000022
   gEfiMdePkgTokenSpaceGuid.PcdUartDefaultStopBits|1|UINT8|0x00000023
   gEfiMdePkgTokenSpaceGuid.PcdDefaultTerminalType|0|UINT8|0x00000024  # 0-PCANSI, 1-VT100, 2-VT00+, 3-UTF8
+  gEfiMdePkgTokenSpaceGuid.PcdPciExpressBaseAddress|0xE0000000|UINT64|0x0000000a