diff --git a/requirements.txt b/requirements.txt
index b1029ac..a93158d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,7 +2,7 @@
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
 beautifulsoup4>=4.6.0 # MIT
-lxml!=3.7.0,>=2.3 # BSD
+lxml!=3.7.0,>=3.4.1 # BSD
 oslo.log>=3.30.0 # Apache-2.0
 requests>=2.14.2 # Apache-2.0
 six>=1.9.0 # MIT