Convenient,　efficient　and　anonymous　characteristic　enables　P2P　network　to　own　enormous　users　very　quickly.　However,　how　much　service　performance　of　searching　and　transmitting　is　provided　by　P2P　network　for　a　concrete　resource?　How　much　is　the　success　ratio　and　recall　ratio　of　resource＇s　searching　of　existing　P2P　network?　Rare　research　is　deepened　bout　those　questions.　This　paper,　for　unstructured　P2P　network,　provides　calculating　method　of　service　performance　of　concrete　resource;　analyzes　success　ratio　and　recall　ratio　of　resource＇s　searching,　and　by　experiment　simulation,　discusses　the　influence　of　resource＇s　popularity,　Peer＇s　quantity,　initial　number　of　objected　resource,　Peer＇s　average　degree　and　TTL　value　to　success　ratio　and　recall　ratio　of　resource＇s　searching.　We　conclude　that　recall　ratio　is　only　related　with　topology　character　of　P2P　network　itself　but　not　related　with　resource＇s　quantity.　Otherwise,　when　TTL　=　4　,　mostly　searching　process　can　reach　higher　success　ratio　and　recall　ratio.　©　2009　IEEE.