diff --git a/setup.py b/setup.py
index b6bbb22dc6956eecce11131a72f84d214cec44e6..7fb0ad4527caf90ba6972b9879454922e38880b6 100644
--- a/setup.py
+++ b/setup.py
@@ -56,7 +56,7 @@ def main():
               "leap>=2015.1",
               "dagrt>=2015.1",
 
-              "six>=1.6",
+              "six>=1.8",
               ])