Abstract: The deployment and the peer selection strategy of BitTorrent(BT) system are studied;the reasons of the stress to the backbone net from BT system are discussed;and an efficient topology conglomeration peer selection strategy is proposed,by which the peers selection is based on the topology information of network.The simulation work has also been done;and it is proved that the new strategy is useful to replace the current BT strategy;and at the same time it can reduce the traffics of the backbone network effectively.