diff --git a/UefiTestingPkg/FunctionalSystemTests/MemmapAndMatTestApp/MemmapAndMatTestApp.c b/UefiTestingPkg/FunctionalSystemTests/MemmapAndMatTestApp/MemmapAndMatTestApp.c
index 30d372ff00..91cb8b27e1 100644
--- a/UefiTestingPkg/FunctionalSystemTests/MemmapAndMatTestApp/MemmapAndMatTestApp.c
+++ b/UefiTestingPkg/FunctionalSystemTests/MemmapAndMatTestApp/MemmapAndMatTestApp.c
@@ -605,6 +605,8 @@ InitializeTestEnvironment (
     return EFI_UNSUPPORTED;
   }
 
+  // Allocate extra memory in case this allocation caused the memory to change.
+  MapSize     += SIZE_1KB;
   EfiMemoryMap = AllocateZeroPool (MapSize);
   if (!EfiMemoryMap) {
     return EFI_OUT_OF_RESOURCES;