diff --git a/tox.ini b/tox.ini
index 7847c6e5..97356b28 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-minversion = 1.6
+minversion = 3.1.1
 envlist = py38,pep8
 skipsdist = True
 ignore_basepython_conflict = true