diff --git a/requirements.txt b/requirements.txt
index 3a460da..b239dab 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -3,7 +3,7 @@ Jinja2==2.7.3
 LEPL==5.1.3
 MarkupSafe==0.23
 PasteDeploy==1.5.2
-PyYAML==3.11
+PyYAML==4.2b1
 Pygments==2.0.2
 Sphinx==1.3.1
 WebOb==1.4.1