diff --git a/tox.ini b/tox.ini
index 176dab62..e29c1fe3 100644
--- a/tox.ini
+++ b/tox.ini
@@ -7,7 +7,7 @@ ignore_basepython_conflict = true
 basepython = python3
 usedevelop = False
 deps =
-    -c{env:UPPER_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/upper-constraints.txt}
+    -c{env:TOX_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/upper-constraints.txt}
     -r{toxinidir}/test-requirements.txt
     -r{toxinidir}/requirements.txt
     -r{toxinidir}/doc/requirements.txt