diff --git a/requirements.txt b/requirements.txt
index 77258f8..e2b5449 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -7,7 +7,7 @@ gevent==1.1.2
 greenlet==0.4.10
 jcconv==0.2.3
 Jinja2==2.8
-lxml==3.5.0
+lxml==4.9.1
 Mako==1.0.4
 MarkupSafe==0.23
 mock==2.0.0