diff --git a/requirements_dev.txt b/requirements_dev.txt
index 7373e91..2f87646 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -7,5 +7,5 @@ tox==2.5.0
 coverage==4.3.1
 Sphinx==1.5.1
 cryptography==1.7.1
-PyYAML==3.12
+PyYAML==6.0.2
 pytest==3.0.5