diff --git a/EdkModulePkg/Library/EdkUefiRuntimeLib/Common/RuntimeLib.c b/EdkModulePkg/Library/EdkUefiRuntimeLib/Common/RuntimeLib.c
index adddf933e2..d80a71cda2 100644
--- a/EdkModulePkg/Library/EdkUefiRuntimeLib/Common/RuntimeLib.c
+++ b/EdkModulePkg/Library/EdkUefiRuntimeLib/Common/RuntimeLib.c
@@ -119,6 +119,7 @@ Returns:
 }
 
 EFI_STATUS
+EFIAPI
 RuntimeDriverLibConstruct (
   IN EFI_HANDLE           ImageHandle,
   IN EFI_SYSTEM_TABLE     *SystemTable
@@ -177,6 +178,7 @@ Returns:
 }
 
 EFI_STATUS
+EFIAPI
 RuntimeDriverLibDeconstruct (
   VOID
   )
diff --git a/EdkModulePkg/Library/EdkUefiRuntimeLib/Ipf/RuntimeLib.c b/EdkModulePkg/Library/EdkUefiRuntimeLib/Ipf/RuntimeLib.c
index a4eeb33838..d0f0d6012b 100644
--- a/EdkModulePkg/Library/EdkUefiRuntimeLib/Ipf/RuntimeLib.c
+++ b/EdkModulePkg/Library/EdkUefiRuntimeLib/Ipf/RuntimeLib.c
@@ -117,6 +117,7 @@ Returns:
 }
 
 EFI_STATUS
+EFIAPI
 RuntimeDriverLibConstruct (
   IN EFI_HANDLE           ImageHandle,
   IN EFI_SYSTEM_TABLE     *SystemTable
@@ -194,6 +195,7 @@ Returns:
 }
 
 EFI_STATUS
+EFIAPI
 RuntimeDriverLibDeconstruct (
   VOID
   )