A method and device for providing a message in a remote User Interface (UI) system are provided. The method includes, if a notification message to be sent to a second device connected to a first device is generated in a remote server or the first device communicating with the remote server, the first device generates access information to the notification message, includes the access information in a notification message event indicating occurrence of the notification message, and sends the notification message event to a plurality of second devices in a multicast transmission. Upon receiving a request for the notification message from the plurality of second devices, the first device sends the notification message to the second device whose IDentifier (ID) is identical to a device ID included in the access information, among the plurality of second devices.