diff --git a/requirements_dev.txt b/requirements_dev.txt
index f04bbf7..9f98856 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -7,7 +7,7 @@ tox==2.9.1
 coverage==4.4.2
 Sphinx==1.6.5
 cryptography==2.1.3
-PyYAML==3.12
+PyYAML==5.1
 pytest==3.2.5
 pytest-runner==3.0
 requests==2.18.4
\ No newline at end of file