diff --git a/requirements.txt b/requirements.txt
index 3e43af7..5b5b2d6 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -30,7 +30,7 @@ Keras==2.2.4
 Keras-Applications==1.0.8
 Keras-Preprocessing==1.1.0
 kiwisolver==1.1.0
-lxml==4.3.4
+lxml==4.9.1
 MarkupSafe==1.1.1
 matplotlib==3.1.0
 mistune==0.8.4