diff --git a/BaseTools/Scripts/PatchCheck.py b/BaseTools/Scripts/PatchCheck.py
index 527761986d..52244b0bc4 100755
--- a/BaseTools/Scripts/PatchCheck.py
+++ b/BaseTools/Scripts/PatchCheck.py
@@ -20,6 +20,8 @@ import re
 import subprocess
 import sys
 
+import email.header
+
 class Verbose:
     SILENT, ONELINE, NORMAL = range(3)
     level = NORMAL