diff --git a/requirements.txt b/requirements.txt
index ef9ed2c..c5b1b1d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -3,7 +3,7 @@ et-xmlfile==1.0.1
 future==0.17.1
 html2text==2019.8.11
 jdcal==1.4.1
-lxml==4.4.1
+lxml==4.9.1
 numpy==1.15.4
 openpyxl==2.6.3
 pandas==0.23.4