diff --git a/requirements.txt b/requirements.txt
index 2059d73f3f..ed562fc807 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -25,7 +25,7 @@ python-cinderclient>=1.0.6
 python-neutronclient>=2.3.4,<3
 python-glanceclient>=0.9.0
 python-keystoneclient>=0.7.0
-six>=1.5.2
+six>=1.6.0
 stevedore>=0.14
 websockify>=0.5.1,<0.6
 wsgiref>=0.1.2