diff --git a/MdeModulePkg/Core/Dxe/Mem/Page.c b/MdeModulePkg/Core/Dxe/Mem/Page.c
index 41af50b3d5..6497af5733 100644
--- a/MdeModulePkg/Core/Dxe/Mem/Page.c
+++ b/MdeModulePkg/Core/Dxe/Mem/Page.c
@@ -1210,7 +1210,7 @@ FindFreePages (
               );
     if (Start != 0) {
       if (Start < mDefaultBaseAddress) {
-        mDefaultBaseAddress = Start;
+        mDefaultBaseAddress = NeedGuard ? Start - EFI_PAGE_SIZE : Start;
       }
 
       return Start;