diff --git a/requirements_dev.txt b/requirements_dev.txt
index 5ab5b7b..42f0162 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -7,5 +7,5 @@ tox==2.7.0
 coverage==4.4.1
 Sphinx==1.7.2
 cryptography==1.9
-PyYAML==3.12
+PyYAML==5.4