Abstract: To counter the attack and propagation of passive worms in large-scale peer-to-peer(P2P) file-sharing networks, three propagating models of passive worms suitable for different stages of worm propagation, are proposed based on deep analysis on the features of file sharing and passive worm propagation. In order to verify the validity of the three modes, large scale simulating experiments are carried out. To simulate the true popular P2P file-sharing networks, a simulating software is developed based on the P2P simulating platform PeerSim. Theory analysis and simulation show that these models are valid and can predict the tendency and behaviors of worm propagation.