1. A peer-to-peer networking method for integrating heterogeneous social networks, applied in a server device, comprising: connecting with a plurality peer nodes, each of the peer node defining a user end and accessing at least one social network; and according to a social relationship of the social networks to link the other corresponding peer nodes for integrating a peer-to-peer social network (P2P-iSN) which configures a plurality of social paths among the peer nodes from the different social networks.