diff --git a/tests/requirements.txt b/tests/requirements.txt
index 7471728..589a759 100644
--- a/tests/requirements.txt
+++ b/tests/requirements.txt
@@ -9,6 +9,6 @@ pycodestyle==2.5.0
 pyflakes==2.1.1
 pytest==5.3.5
 pytest-cov==2.8.1
-pytest-mock==3
+pytest-mock==3.1.0
 pytest-sugar==0.9.2
 twine==3.1.1