diff --git a/tools/tests-requirements.txt b/tools/tests-requirements.txt
index 8c9bd759207..75e810980fd 100644
--- a/tools/tests-requirements.txt
+++ b/tools/tests-requirements.txt
@@ -1,7 +1,7 @@
 freezegun
 mock
 pretend
-pytest
+pytest==3.8.2
 pytest-cov
 pytest-rerunfailures
 pytest-timeout