diff --git a/synapse/python_dependencies.py b/synapse/python_dependencies.py
index 987eec3ef2d92e5877ce758dd881ccdee4ff8ff6..9c55e79ef5feefb94d6780dc5accf308d8463ec4 100644
--- a/synapse/python_dependencies.py
+++ b/synapse/python_dependencies.py
@@ -39,7 +39,7 @@ REQUIREMENTS = {
     "signedjson>=1.0.0": ["signedjson>=1.0.0"],
     "pynacl>=1.2.1": ["nacl>=1.2.1", "nacl.bindings"],
     "service_identity>=1.0.0": ["service_identity>=1.0.0"],
-    "Twisted>=16.0.0": ["twisted>=16.0.0"],
+    "Twisted>=17.1.0": ["twisted>=17.1.0"],
 
     # We use crypto.get_elliptic_curve which is only supported in >=0.15
     "pyopenssl>=0.15": ["OpenSSL>=0.15"],