diff --git a/MdePkg/Include/Library/PrintLib.h b/MdePkg/Include/Library/PrintLib.h
index e47dbae5e0..1158a47b15 100644
--- a/MdePkg/Include/Library/PrintLib.h
+++ b/MdePkg/Include/Library/PrintLib.h
@@ -473,10 +473,10 @@ AsciiSPrintUnicodeFormat (
 UINTN
 EFIAPI
 AsciiValueToString (
-  IN OUT CHAR8  *Buffer,
-  IN UINTN      Flags,
-  IN INT64      Value,
-  IN UINTN      Width
+  OUT CHAR8      *Buffer,
+  IN  UINTN      Flags,
+  IN  INT64      Value,
+  IN  UINTN      Width
   );
 
 #endif
diff --git a/MdePkg/Library/BasePrintLib/PrintLib.c b/MdePkg/Library/BasePrintLib/PrintLib.c
index 92deb5f5db..d08024758a 100644
--- a/MdePkg/Library/BasePrintLib/PrintLib.c
+++ b/MdePkg/Library/BasePrintLib/PrintLib.c
@@ -492,10 +492,10 @@ AsciiSPrintUnicodeFormat (
 UINTN
 EFIAPI
 AsciiValueToString (
-  IN OUT CHAR8  *Buffer,
-  IN UINTN      Flags,
-  IN INT64      Value,
-  IN UINTN      Width
+  OUT CHAR8      *Buffer,
+  IN  UINTN      Flags,
+  IN  INT64      Value,
+  IN  UINTN      Width
   )
 {
   return BasePrintLibConvertValueToString (Buffer, Flags, Value, Width, 1);