diff --git a/requirements.txt b/requirements.txt
index d1c35ee..7647ae5 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,7 +1,7 @@
 certifi==2019.3.9
 chardet==3.0.4
 idna==2.8
-lxml==4.3.3
+lxml==4.9.1
 pymarc==3.1.13
 requests==2.21.0
 Sickle==0.6.4