An　increasing　number　of　Peer-to-Peer　(P2P)　applications　are　appeared.　The　defect　of　P2P　network　which　causes　several　security　problems　must　be　in　focus.　In　this　paper,　a　model　of　trusted　P2P　network　will　be　introduced,　which　integrates　the　security　mechanisms　about　integrity　measurement,　authorization,　authentication　and　encryption.　It　can　make　a　good　security　performance　on　centralized　topology　P2P　network　and　establish　the　foundation　of　further　P2P　network　application.