diff --git a/requirements.txt b/requirements.txt
index aa260b3..37df2bc 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,5 @@
 google-auth==1.6.3
 google-api-python-client==1.7.11
-icalendar==4.0.3
+icalendar==4.0.4
 pytz==2019.3
 PyYAML==5.1.2