diff --git a/PcAtChipsetPkg/8259InterruptControllerDxe/8259.c b/PcAtChipsetPkg/8259InterruptControllerDxe/8259.c
index 447106afe9..e73a1007a2 100644
--- a/PcAtChipsetPkg/8259InterruptControllerDxe/8259.c
+++ b/PcAtChipsetPkg/8259InterruptControllerDxe/8259.c
@@ -123,8 +123,10 @@ Interrupt8259SetVectorBase (
   IN UINT8                     SlaveBase
   )
 {
-  UINT8 Mask;
+  UINT8   Mask;
+  EFI_TPL OriginalTpl;
 
+  OriginalTpl = gBS->RaiseTPL (TPL_HIGH_LEVEL);
   //
   // Set vector base for slave PIC
   //
@@ -211,6 +213,8 @@ Interrupt8259SetVectorBase (
 
   IoWrite8 (LEGACY_8259_CONTROL_REGISTER_SLAVE, LEGACY_8259_EOI);
   IoWrite8 (LEGACY_8259_CONTROL_REGISTER_MASTER, LEGACY_8259_EOI);
+  
+  gBS->RestoreTPL (OriginalTpl);
 
   return EFI_SUCCESS;
 }