diff --git a/requirements.txt b/requirements.txt
index 71fb578a..ccf4a4e1 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -29,6 +29,7 @@ bleach==1.4
 django-ipware==0.1.0
 premailer==2.8.1
 django-transactional-cleanup==0.1.12
+lxml==3.4.1
 
 # Comment it if you are using python >= 3.4
 enum34==1.0