diff --git a/BaseTools/Source/Python/GenFds/Region.py b/BaseTools/Source/Python/GenFds/Region.py
index 7548a4f014..e393286a16 100644
--- a/BaseTools/Source/Python/GenFds/Region.py
+++ b/BaseTools/Source/Python/GenFds/Region.py
@@ -56,7 +56,7 @@ class Region(RegionClassObject):
                 PadByte = pack('B', 0xFF)
             else:
                 PadByte = pack('B', 0)
-            PadData = string.join(PadByte for i in xrange(0, Size))
+            PadData = ''.join(PadByte for i in xrange(0, Size))
             Buffer.write(PadData)
 
     ## AddToBuffer()