Multicast delivery has become more and more important in modern multimedia applications for broadband satellites over ATM networks. Multimedia integrates texts, audios, videos and still images in a variety of applications. The data in this media can be time critical in terms of maximum delay and delay jitter. In order to satisfy all these applications, the network needs to have an efficient multicasting mechanism using the true capability of ATM networks. In this paper, a bi-directional multipoint-to-multipoint multicast model was proposed for broadband multimedia satellites over ATM networks, which uses a single tree for a multicast group consisting of multiple participants that are either senders, receivers, or a mix of both. We first discuss why the resequencer model will not be suitable for multimedia traffics, then propose the model to solve the problems. The mean queueing delays of our model are not sensitive to mean size of the data packet while the mean queueing delays and of the resequencer model are very sensitive to mean size of the data packet.