diff --git a/zoho/requirements.txt b/zoho/requirements.txt
index 0df06bc..f3c3488 100644
--- a/zoho/requirements.txt
+++ b/zoho/requirements.txt
@@ -10,7 +10,7 @@ pyasn1-modules==0.0.8
 pyparsing==2.2.0
 python-dateutil==2.6.0
 pytz==2017.2
-PyYAML==3.13
+PyYAML==5.1
 requests==2.13.0
 rsa==3.4.2
 six==1.10.0