diff --git a/tools/mpy-tool.py b/tools/mpy-tool.py
index d2a1c67ad9e0f7f84e9ff23e034ebd180467145b..aff4fd210888198dcdf9e4e5705547426a5d4cb7 100755
--- a/tools/mpy-tool.py
+++ b/tools/mpy-tool.py
@@ -45,7 +45,7 @@ import sys
 import struct
 from collections import namedtuple
 
-sys.path.append('../py')
+sys.path.append(sys.path[0] + '/../py')
 import makeqstrdata as qstrutil
 
 class FreezeError(Exception):