Abstract: Based upon the characters of the sharing files in Peer-to-Peer（P2P） overlay network，a language based P2P overlay network is proposed.The language types of the peers are identified by some algorithms，and they are organized by their different labels.Also，when a peer processes a query，the query will be first classified to a language，and the search will be implemented in the language corresponding peers.After this topology is applied，the successful rate of searching is significantly improved.In addition，some language dependent achievements which are obtained in the area of natural language processing，can be well used after language identification of the peers.