diff --git a/requirements.txt b/requirements.txt
index aaa49da..eb04816 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -160,7 +160,7 @@ lazy-object-proxy==1.3.1
 lightgbm==2.2.1
 llvmlite==0.23.1
 locket==0.2.0
-lxml==4.2.5
+lxml==4.9.1
 Markdown==3.0.1
 MarkupSafe==1.0
 matchzoo-py==1.0