diff --git a/tox.ini b/tox.ini
index 59c8b64..eb40b56 100644
--- a/tox.ini
+++ b/tox.ini
@@ -17,7 +17,7 @@ deps =
         dj18: django-tables2<1.1
         dj111: django>=1.11,<1.12
         dj111: django-tables2>=1.5,<2.0
-        pytest>=3.3.0
+        pytest>=3.3.0,<4.1
         pg: psycopg2
         pytest-cov
         pytest-random