diff --git a/tox.ini b/tox.ini
index e3eeb8645..84eef706f 100644
--- a/tox.ini
+++ b/tox.ini
@@ -4,7 +4,7 @@ skipsdist = True
 envlist = releasenotes
 
 [testenv]
-install_command = pip install -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt} {opts} {packages}
+install_command = pip install -c{env:TOX_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt} {opts} {packages}
 
 [testenv:releasenotes]
 basepython = python3