diff --git a/requirements.txt b/requirements.txt
index 596cbb6..e5284cc 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,7 +2,7 @@ alabaster==0.7.2
 Babel==1.3
 docutils==0.12
 Jinja2==2.7.3
-lxml==3.4.2
+lxml==6.1.0
 MarkupSafe==0.23
 Pygments==2.0.2
 python-dateutil==2.4.1