diff --git a/tox.ini b/tox.ini
index a052d9e..81e24ca 100644
--- a/tox.ini
+++ b/tox.ini
@@ -12,7 +12,7 @@ setenv = VIRTUAL_ENV={envdir}
          NOSE_OPENSTACK_RED=0.05
          NOSE_OPENSTACK_YELLOW=0.025
          NOSE_OPENSTACK_SHOW_ELAPSED=1
-deps = -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+deps = -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
        -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
 commands =