diff --git a/tox.ini b/tox.ini
index 0823d5a..514c06c 100644
--- a/tox.ini
+++ b/tox.ini
@@ -20,7 +20,7 @@ deps =
   pg: psycopg2
   mock
   httmock
-  pytest
+  pytest<4.1
   pytest-cov
   pytest-random
   pytest-mock