Communication method, terminals and system applied in multiple networks

The present invention provides a multi-network application communication method, terminal and system, wherein the method comprises: the calling terminal by presenting its registration server to obtain presence information of the called terminal, and based on the information presented is determined for characterizing the called terminal network application identifying the communication path, wherein each network application identification corresponds with each contact; calling terminal presented in accordance with their registration server and the default priority for each network applications, determine network application to initiate communication; initiating the communication network applications to establish communication between the calling terminal and the called terminal based on network application identification. The present invention is useful for service termination of two different mechanisms to achieve only need to maintain a set of contacts, to avoid the application of each network contacts unrelated existing terminal, a terminal multiple sets of data, low operating efficiency of defect; while achieving each network application interoperability and communication based on user reluctance degrees.