diff --git a/tox.ini b/tox.ini
index 5ef92582977..362036c8d20 100644
--- a/tox.ini
+++ b/tox.ini
@@ -20,7 +20,7 @@ commands =
 
 [testenv:common]
 # Fake job to define environment variables shared between dsvm/non-dsvm jobs
-setenv = OS_TEST_TIMEOUT=180
+setenv = OS_TEST_TIMEOUT={env:OS_TEST_TIMEOUT:180}
 commands = false
 
 [testenv:dsvm]
@@ -72,7 +72,7 @@ setenv = {[testenv]setenv}
          {[testenv:common]setenv}
          {[testenv:dsvm]setenv}
          # workaround for DB teardown lock contention (bug/1541742)
-         OS_TEST_TIMEOUT=600
+         OS_TEST_TIMEOUT={env:OS_TEST_TIMEOUT:600}
          OS_TEST_PATH=./neutron/tests/fullstack
 deps =
   {[testenv:functional]deps}