diff --git a/ArmPkg/Library/ArmArchTimerLib/ArmArchTimerLib.c b/ArmPkg/Library/ArmArchTimerLib/ArmArchTimerLib.c
index 5d8e006cc9..c0ab4a4433 100644
--- a/ArmPkg/Library/ArmArchTimerLib/ArmArchTimerLib.c
+++ b/ArmPkg/Library/ArmArchTimerLib/ArmArchTimerLib.c
@@ -85,7 +85,7 @@ MicroSecondDelay (
   // Calculate counter ticks that can represent requested delay:
   //  = MicroSeconds x TICKS_PER_MICRO_SEC
   //  = MicroSeconds x Frequency.10^-6
-  TimerTicks64 = (MicroSeconds * PcdGet32 (PcdArmArchTimerFreqInHz)) / 1000000U;
+  TimerTicks64 = ((UINT64)MicroSeconds * PcdGet32 (PcdArmArchTimerFreqInHz)) / 1000000U;
 
   // Read System Counter value
   SystemCounterVal = ArmGenericTimerGetSystemCount ();