diff --git a/requirements_dev.txt b/requirements_dev.txt
index 65380a10..8061b604 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -8,6 +8,6 @@ coverage==4.4.1
 Sphinx==1.6.3
 cryptography==2.0.3
 PyYAML==3.12
-pytest
+pytest==3.2.2
 mypy
 hypothesis