diff --git a/synapse/python_dependencies.py b/synapse/python_dependencies.py
index 826a36f203ab9c40a48bf58e889cb7dc298accd1..168fab06581cef518146544007ba9423e091abc2 100644
--- a/synapse/python_dependencies.py
+++ b/synapse/python_dependencies.py
@@ -16,6 +16,7 @@ REQUIREMENTS = {
     "py-bcrypt": ["bcrypt"],
     "frozendict>=0.4": ["frozendict"],
     "pillow": ["PIL"],
+    "pydenticon": ["pydenticon"],
 }