diff --git a/libp2p/pubsub/pubsub.py b/libp2p/pubsub/pubsub.py
index 31ce4c7..671df9b 100644
--- a/libp2p/pubsub/pubsub.py
+++ b/libp2p/pubsub/pubsub.py
@@ -161,7 +161,7 @@ class Pubsub:
             # Force context switch
             await asyncio.sleep(0)
 
-    def add_topic_validator(
+    def set_topic_validator(
         self, topic: str, validator: ValidatorFn, is_async_validator: bool
     ) -> None:
         self.topic_validators[topic] = TopicValidator(validator, is_async_validator)
diff --git a/tests/pubsub/test_pubsub.py b/tests/pubsub/test_pubsub.py
index 530677b..438c48b 100644
--- a/tests/pubsub/test_pubsub.py
+++ b/tests/pubsub/test_pubsub.py
@@ -84,6 +84,54 @@ async def test_get_hello_packet(pubsubs_fsub):
         assert topic in topic_ids_in_hello
 
 
+@pytest.mark.parametrize("num_hosts", (1,))
+@pytest.mark.asyncio
+async def test_add_topic_validator(pubsubs_fsub):
+
+    is_sync_validator_called = False
+
+    def sync_validator(peer_id, msg):
+        nonlocal is_sync_validator_called
+        is_sync_validator_called = True
+
+    is_async_validator_called = False
+
+    async def async_validator(peer_id, msg):
+        nonlocal is_async_validator_called
+        is_async_validator_called = True
+
+    topic = "TEST_VALIDATOR"
+
+    assert topic not in pubsubs_fsub[0].topic_validators
+
+    # Register sync validator
+    pubsubs_fsub[0].set_topic_validator(topic, sync_validator, False)
+
+    assert topic in pubsubs_fsub[0].topic_validators
+    topic_validator = pubsubs_fsub[0].topic_validators[topic]
+    assert not topic_validator.is_async
+
+    # Validate with sync validator
+    topic_validator.validator(peer_id=ID(b"peer"), msg="msg")
+
+    assert is_sync_validator_called
+    assert not is_async_validator_called
+
+    # Register with async validator
+    pubsubs_fsub[0].set_topic_validator(topic, async_validator, True)
+
+    is_sync_validator_called = False
+    assert topic in pubsubs_fsub[0].topic_validators
+    topic_validator = pubsubs_fsub[0].topic_validators[topic]
+    assert topic_validator.is_async
+
+    # Validate with async validator
+    await topic_validator.validator(peer_id=ID(b"peer"), msg="msg")
+
+    assert is_async_validator_called
+    assert not is_sync_validator_called
+
+
 class FakeNetStream:
     _queue: asyncio.Queue