diff --git a/libp2p/pubsub/gossipsub.py b/libp2p/pubsub/gossipsub.py
index 45c6cd81..e92c457d 100644
--- a/libp2p/pubsub/gossipsub.py
+++ b/libp2p/pubsub/gossipsub.py
@@ -308,7 +308,7 @@ class GossipSub(IPubsubRouter, Service):
             floodsub_peers: set[ID] = {
                 peer_id
                 for peer_id in self.pubsub.peer_topics[topic]
-                if self.peer_protocol[peer_id] == floodsub.PROTOCOL_ID
+                if peer_id in self.peer_protocol and self.peer_protocol[peer_id] == floodsub.PROTOCOL_ID
             }
             send_to.update(floodsub_peers)