diff --git a/EmulatorPkg/FvbServicesRuntimeDxe/FWBlockService.c b/EmulatorPkg/FvbServicesRuntimeDxe/FWBlockService.c
index 44df1172b1..fdffca2c94 100644
--- a/EmulatorPkg/FvbServicesRuntimeDxe/FWBlockService.c
+++ b/EmulatorPkg/FvbServicesRuntimeDxe/FWBlockService.c
@@ -906,7 +906,7 @@ Returns:
       break;
     }
 
-    NumOfLba = VA_ARG (args, UINT32);
+    NumOfLba = VA_ARG (args, UINTN);
 
     //
     // Check input parameters
@@ -926,7 +926,7 @@ Returns:
       break;
     }
 
-    NumOfLba = VA_ARG (args, UINT32);
+    NumOfLba = VA_ARG (args, UINTN);
 
     while (NumOfLba > 0) {
       Status = FvbEraseBlock (FvbDevice->Instance, StartingLba, mFvbModuleGlobal, EfiGoneVirtual ());