diff --git a/tox.ini b/tox.ini
index 33d8afe..5a5377b 100644
--- a/tox.ini
+++ b/tox.ini
@@ -9,7 +9,7 @@ install_command = pip install {opts} {packages}
 whitelist_externals = find
                       rm
 deps =
-       -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+       -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
        -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
 commands =