diff --git a/synapse/python_dependencies.py b/synapse/python_dependencies.py
index 882e844eb1..b5555fbba9 100644
--- a/synapse/python_dependencies.py
+++ b/synapse/python_dependencies.py
@@ -81,7 +81,7 @@ CONDITIONAL_REQUIREMENTS = {
 
     "saml2": ["pysaml2>=4.5.0"],
     "url_preview": ["lxml>=3.5.0"],
-    "test": ["mock>=2.0"],
+    "test": ["mock>=2.0", "parameterized"],
 }
 
 
diff --git a/tox.ini b/tox.ini
index a0f5486829..9b6cb2036c 100644
--- a/tox.ini
+++ b/tox.ini
@@ -8,6 +8,7 @@ deps =
     python-subunit
     junitxml
     coverage
+    parameterized
 
     # cyptography 2.2 requires setuptools >= 18.5
     #