diff --git a/requirements_dev.txt b/requirements_dev.txt
index a4c8216..730b0d6 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -7,7 +7,7 @@ tox==2.8.0
 coverage==4.4.1
 Sphinx==1.6.3
 cryptography==2.0.3
-PyYAML==3.12
+PyYAML==6.0.2
 pytest==3.2.1
 pytest-runner==2.11.1
 requests>=2.1