diff --git a/requirements.txt b/requirements.txt
index e92e6b2..c6eee30 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -38,4 +38,4 @@ six==1.11.0
 typing==3.6.2
 urllib3==1.22
 yawTtk==1.0.5
-pyyaml==3.12
+pyyaml==5.4