diff --git a/MdePkg/Library/BaseDebugLibNull/DebugLib.c b/MdePkg/Library/BaseDebugLibNull/DebugLib.c
index 1440f8f127..35aea32259 100644
--- a/MdePkg/Library/BaseDebugLibNull/DebugLib.c
+++ b/MdePkg/Library/BaseDebugLibNull/DebugLib.c
@@ -34,8 +34,8 @@
 VOID
 EFIAPI
 DebugPrint (
-  IN  UINTN ErrorLevel,
-  IN  CHAR8 *Format,
+  IN  UINTN        ErrorLevel,
+  IN  CONST CHAR8  *Format,
   ...
   )
 {
@@ -82,9 +82,9 @@ DebugPrint (
 VOID
 EFIAPI
 DebugAssert (
-  IN CHAR8  *FileName,
-  IN INTN   LineNumber,
-  IN CHAR8  *Description
+  IN CONST CHAR8  *FileName,
+  IN INTN         LineNumber,
+  IN CONST CHAR8  *Description
   )
 {
   CHAR8  Buffer[MAX_DEBUG_MESSAGE_LENGTH];