diff --git a/MdeModulePkg/Universal/Acpi/S3SaveStateDxe/InternalS3SaveState.h b/MdeModulePkg/Universal/Acpi/S3SaveStateDxe/InternalS3SaveState.h
index 19600085f1..b710919881 100644
--- a/MdeModulePkg/Universal/Acpi/S3SaveStateDxe/InternalS3SaveState.h
+++ b/MdeModulePkg/Universal/Acpi/S3SaveStateDxe/InternalS3SaveState.h
@@ -75,7 +75,7 @@ EFI_STATUS
 EFIAPI
 BootScriptWrite (
   IN CONST EFI_S3_SAVE_STATE_PROTOCOL      *This,
-  IN       UINT16                           OpCode,
+  IN       UINTN                            OpCode,
   ...
   );
 /**
@@ -112,7 +112,7 @@ BootScriptInsert (
   IN CONST EFI_S3_SAVE_STATE_PROTOCOL    *This,
   IN       BOOLEAN                          BeforeOrAfter,
   IN OUT   EFI_S3_BOOT_SCRIPT_POSITION     *Position OPTIONAL,
-  IN       UINT16                           OpCode,
+  IN       UINTN                            OpCode,
   ...
   );
 /**
diff --git a/MdeModulePkg/Universal/Acpi/S3SaveStateDxe/S3SaveState.c b/MdeModulePkg/Universal/Acpi/S3SaveStateDxe/S3SaveState.c
index 274f3be12c..5913078d69 100644
--- a/MdeModulePkg/Universal/Acpi/S3SaveStateDxe/S3SaveState.c
+++ b/MdeModulePkg/Universal/Acpi/S3SaveStateDxe/S3SaveState.c
@@ -542,7 +542,7 @@ EFI_STATUS
 EFIAPI
 BootScriptWrite (
   IN CONST EFI_S3_SAVE_STATE_PROTOCOL      *This,
-  IN       UINT16                           OpCode,
+  IN       UINTN                            OpCode,
   ...
   )
 {
@@ -697,7 +697,7 @@ BootScriptInsert (
   IN CONST EFI_S3_SAVE_STATE_PROTOCOL     *This,
   IN       BOOLEAN                        BeforeOrAfter,
   IN OUT   EFI_S3_BOOT_SCRIPT_POSITION    *Position OPTIONAL,
-  IN       UINT16                         OpCode,
+  IN       UINTN                          OpCode,
   ...
   )
 {