diff --git a/MdeModulePkg/Universal/DevicePathDxe/DevicePathToText.c b/MdeModulePkg/Universal/DevicePathDxe/DevicePathToText.c
index 627d8762a1..e8ee5c5546 100644
--- a/MdeModulePkg/Universal/DevicePathDxe/DevicePathToText.c
+++ b/MdeModulePkg/Universal/DevicePathDxe/DevicePathToText.c
@@ -29,6 +29,7 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
 
 **/
 CHAR16 *
+EFIAPI
 CatPrint (
   IN OUT POOL_PRINT   *Str,
   IN CHAR16           *Fmt,
diff --git a/MdeModulePkg/Universal/EbcDxe/Ipf/EbcSupport.c b/MdeModulePkg/Universal/EbcDxe/Ipf/EbcSupport.c
index cdaae8785b..cf21cc7a21 100644
--- a/MdeModulePkg/Universal/EbcDxe/Ipf/EbcSupport.c
+++ b/MdeModulePkg/Universal/EbcDxe/Ipf/EbcSupport.c
@@ -80,6 +80,7 @@ PushU64 (
 
 **/
 UINT64
+EFIAPI
 EbcInterpret (
   UINT64      Arg1,
   ...
diff --git a/MdeModulePkg/Universal/SetupBrowserDxe/Print.c b/MdeModulePkg/Universal/SetupBrowserDxe/Print.c
index 1f97ed43b6..941d0958f9 100644
--- a/MdeModulePkg/Universal/SetupBrowserDxe/Print.c
+++ b/MdeModulePkg/Universal/SetupBrowserDxe/Print.c
@@ -145,6 +145,7 @@ PrintInternal (
 
 **/
 UINTN
+EFIAPI
 ConsolePrint (
   IN CHAR16   *Fmt,
   ...
@@ -206,6 +207,7 @@ PrintChar (
 
 **/
 UINTN
+EFIAPI
 PrintAt (
   IN UINTN     Column,
   IN UINTN     Row,
diff --git a/MdeModulePkg/Universal/SetupBrowserDxe/Setup.h b/MdeModulePkg/Universal/SetupBrowserDxe/Setup.h
index 51d6b882b7..5239b44caa 100644
--- a/MdeModulePkg/Universal/SetupBrowserDxe/Setup.h
+++ b/MdeModulePkg/Universal/SetupBrowserDxe/Setup.h
@@ -633,6 +633,7 @@ PrintChar (
 
 **/
 UINTN
+EFIAPI
 PrintAt (
   IN UINTN     Column,
   IN UINTN     Row,
@@ -800,6 +801,7 @@ CreateSharedPopUp (
 
 **/
 EFI_STATUS
+EFIAPI
 CreateDialog (
   IN  UINTN                       NumberOfLines,
   IN  BOOLEAN                     HotKey,
diff --git a/MdeModulePkg/Universal/SetupBrowserDxe/Ui.c b/MdeModulePkg/Universal/SetupBrowserDxe/Ui.c
index fecb0248bd..0d3c1ebce8 100644
--- a/MdeModulePkg/Universal/SetupBrowserDxe/Ui.c
+++ b/MdeModulePkg/Universal/SetupBrowserDxe/Ui.c
@@ -678,6 +678,7 @@ UiAddMenuOption (
 
 **/
 EFI_STATUS
+EFIAPI
 CreateDialog (
   IN  UINTN                       NumberOfLines,
   IN  BOOLEAN                     HotKey,
@@ -978,6 +979,7 @@ CreateSharedPopUp (
 
 **/
 VOID
+EFIAPI
 CreateMultiStringPopUp (
   IN  UINTN                       RequestedWidth,
   IN  UINTN                       NumberOfLines,
diff --git a/MdeModulePkg/Universal/SetupBrowserDxe/Ui.h b/MdeModulePkg/Universal/SetupBrowserDxe/Ui.h
index cdd661ca99..362f8e7d60 100644
--- a/MdeModulePkg/Universal/SetupBrowserDxe/Ui.h
+++ b/MdeModulePkg/Universal/SetupBrowserDxe/Ui.h
@@ -389,6 +389,7 @@ UiWaitForSingleEvent (
 
 **/
 VOID
+EFIAPI
 CreateMultiStringPopUp (
   IN  UINTN                       ScreenWidth,
   IN  UINTN                       NumberOfLines,