diff --git a/requirements.txt b/requirements.txt
index 24449c4..0d1e0f9 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -91,7 +91,7 @@ kiwisolver==1.0.1
 lazy-object-proxy==1.3.1
 llvmlite==0.24.0
 locket==0.2.0
-lxml==3.5.0
+lxml==4.6.2
 Mako==1.0.7
 MarkupSafe==1.0
 matplotlib==2.2.2