Lack　of　trust　between　peers　is　one　of　the　most　Serious　drawbacks　that　obstruct　the　wide　adoption　of　mobile　p2p　systems.　Since　Current　reputation　schemes　developed　mainly　for　the　fixed　wired　networks　are　not　fit　in　Such　a　scenario,　new　trust　Solutions　are　eagerly　in　demand.　This　paper　presents　a　power　peer-based　reputation　scheme,　where　peers　are　classified　into　two　groups,　power　peers　and　mobile　peers　and　a　power　peer　has　zero　or　more　mobile　peers.　We　design　two　ways　of　selecting　power　peers,　greedy　method　and　maximal　independent　set　method.　The　proposed　scheme　establishes　a　trusted　mobile　environment　for　mobile　p2p　systems.　It　effectively　avoids　the　Communication　overhead　ill　global　trust　computation　because　each　power　peer　maintains　the　appropriate　reptuation　information　of　its　mobile　peers.　The　simulation　results　show　that　our　scheme　is　highly　robust　and　scalable　in　the　dynamic　environment　of　mobile　networks.