when　mobile　users　search　points　of　interest　from　location　based　service,　they　always　should　provide　their　accurate　locations,　which　may　leak　users＇　location　privacy.　To　protect　users＇　location　privacy,　some　two-tie　approaches　have　been　imposed.　However,　existing　approaches　are　either　hard　to　implement　or　may　lead　to　high　communication　cost.　In　this　paper,　we　present　a　novel　approach,　called　Guess-Answer.　Through　the　interaction　between　the　user　and　the　server,　a　cloaked　region,　which　satisfies　the　user＇s　personal　privacy　requirement,　can　be　generated.　The　experimental　results　show　that　our　approaches　are　scalable　and　robust.　©　2011　IEEE.