diff --git a/requirements.txt b/requirements.txt
index 9187b91..ef04308 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -15,7 +15,7 @@ elasticsearch==2.1.0
 gevent==1.0.1
 greenlet==0.4.5
 itsdangerous==0.24
-lxml==3.4.2
+lxml==4.9.1
 matplotlib==1.5.0
 mechanize==0.2.5
 numpy==1.10.1