diff --git a/contrib/zmq/zmq_sub.py b/contrib/zmq/zmq_sub.py
index d8087a4db38..b2290a6c5b6 100755
--- a/contrib/zmq/zmq_sub.py
+++ b/contrib/zmq/zmq_sub.py
@@ -7,7 +7,7 @@
     ZMQ example using python3's asyncio
 
     Bitcoin should be started with the command line arguments:
-        bitcoind -testnet -daemon \
+        bitcoind -testnet4 -daemon \
                 -zmqpubrawtx=tcp://127.0.0.1:28332 \
                 -zmqpubrawblock=tcp://127.0.0.1:28332 \
                 -zmqpubhashtx=tcp://127.0.0.1:28332 \