diff --git a/requirements.txt b/requirements.txt
index 270ac02..13b6206 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -39,7 +39,7 @@ iso8601==0.1.10
 isodate==0.5.1
 jsonpickle==0.9.4
 kombu==3.0.35
-lxml==3.7.2
+lxml==4.6.5
 Markdown==2.6.2
 mock==2.0.0
 networkx==1.10