diff --git a/setup.py b/setup.py
index e0bd45457..e76fed2bf 100644
--- a/setup.py
+++ b/setup.py
@@ -71,7 +71,7 @@ setup(
         "h2>=2.4.0, <3",
         "html2text>=2016.1.8, <=2016.5.29",
         "hyperframe>=4.0.1, <5",
-        "lxml>=3.5.0, <3.7",
+        "lxml>=3.5.0, <=3.6.0",  # no wheels for 3.6.1 yet.
         "Pillow>=3.2, <3.4",
         "passlib>=1.6.5, <1.7",
         "pyasn1>=0.1.9, <0.2",