diff --git a/Recognizer/Recognizer.Lib/requirements.txt b/Recognizer/Recognizer.Lib/requirements.txt
index 35d15ad..f1077b0 100644
--- a/Recognizer/Recognizer.Lib/requirements.txt
+++ b/Recognizer/Recognizer.Lib/requirements.txt
@@ -4,7 +4,7 @@ mock==2.0.0
 numpy==1.11.1
 pbr==3.1.1
 protobuf==3.3.0
-PyYAML==3.12
+PyYAML==5.1
 scikit-learn==0.18.2
 scipy==0.19.1
 six==1.10.0