diff --git a/requirements.txt b/requirements.txt
index 0ec8267..b39d5f1 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -34,7 +34,7 @@ python-coveralls==2.9.1
 python-dateutil==2.7.3
 python-igraph==0.7.1.post6
 pytz==2018.5
-PyYAML==3.13
+PyYAML==5.3.1
 requests==2.20.0
 scipy==1.1.0
 simplegeneric==0.8.1