diff --git a/ArmPkg/Drivers/ArmGic/ArmGicLib.c b/ArmPkg/Drivers/ArmGic/ArmGicLib.c
index eca4ddb7d3..eefe6350eb 100644
--- a/ArmPkg/Drivers/ArmGic/ArmGicLib.c
+++ b/ArmPkg/Drivers/ArmGic/ArmGicLib.c
@@ -111,7 +111,7 @@ GicGetCpuRedistributorBase (
 
   @retval CPU Interface Identification information.
 **/
-UINTN
+UINT32
 EFIAPI
 ArmGicGetInterfaceIdentification (
   IN  UINTN  GicInterruptInterfaceBase
diff --git a/ArmPkg/Include/Library/ArmGicLib.h b/ArmPkg/Include/Library/ArmGicLib.h
index cede7a24b7..93ce8aeb19 100644
--- a/ArmPkg/Include/Library/ArmGicLib.h
+++ b/ArmPkg/Include/Library/ArmGicLib.h
@@ -110,7 +110,7 @@
 // Bit Mask for
 #define ARM_GIC_ICCIAR_ACKINTID  0x3FF
 
-UINTN
+UINT32
 EFIAPI
 ArmGicGetInterfaceIdentification (
   IN  UINTN  GicInterruptInterfaceBase