diff --git a/requirements_dev.txt b/requirements_dev.txt
index 1b926172..3e2cdf61 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -7,7 +7,7 @@ tox==2.9.1
 coverage==4.5.1
 Sphinx==1.6.6
 cryptography==2.1.4
-PyYAML==3.12
+PyYAML==4.1
 pytest==3.4.0
 pytest-runner==3.0
 pytest-cov==2.5.1