diff --git a/socketio/asyncio_server.py b/socketio/asyncio_server.py
index 0115a47d..9b41a698 100644
--- a/socketio/asyncio_server.py
+++ b/socketio/asyncio_server.py
@@ -362,8 +362,10 @@ async def _emit_internal(self, sid, event, data, namespace=None, id=None):
         # as a single argument
         if isinstance(data, tuple):
             data = list(data)
-        else:
+        elif data is not None:
             data = [data]
+        else:
+            data = []
         await self._send_packet(sid, packet.Packet(
             packet.EVENT, namespace=namespace, data=[event] + data, id=id,
             binary=None))
diff --git a/socketio/server.py b/socketio/server.py
index 8848de72..24445261 100644
--- a/socketio/server.py
+++ b/socketio/server.py
@@ -573,8 +573,10 @@ def _emit_internal(self, sid, event, data, namespace=None, id=None):
         # as a single argument
         if isinstance(data, tuple):
             data = list(data)
-        else:
+        elif data is not None:
             data = [data]
+        else:
+            data = []
         self._send_packet(sid, packet.Packet(packet.EVENT, namespace=namespace,
                                              data=[event] + data, id=id,
                                              binary=binary))