diff --git a/requirements.txt b/requirements.txt
index cb23ad5..4c91469 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -22,7 +22,7 @@ flake8==3.5.0
 funcsigs==1.0.2           # via mock, pytest
 idna==2.6                 # via requests
 isodate==0.6.0            # via zeep
-lxml==4.1.1               # via zeep
+lxml==4.6.2               # via zeep
 mccabe==0.6.1             # via flake8
 mock==2.0.0               # via pip-conflict-checker
 nose==1.3.7               # via pip-conflict-checker