diff --git a/requirements.txt b/requirements.txt
index a21350f..f8a34aa 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -14,7 +14,7 @@ hpack==2.0.1
 html2text==2015.11.4
 idna==2.0
 ipaddress==1.0.16
-lxml==3.4.4
+lxml==4.9.1
 mitmproxy==0.15
 ndg-httpsclient==0.4.0
 netlib==0.15.1