Nowadays,　mobile　phones　are　often　used　as　an　attractive　option　for　large-scale　sensing　of　human　behavior,　providing　a　source　of　real　and　reliable　data　for　urban　computing.　As　it　is　known　to　all,　a　user＇s　behavior　often　happened　at　some　places　where　the　user　stayed　over　a　certain　time　interval　for　a　trip.　For　understanding　a　user＇s　behavior　effectively,　we　need　to　detect　the　places　where　the　user　stayed　over　a　certain　time　interval　and　we　call　these　places　stay　areas.　In　this　paper,　we　propose　a　method　for　detecting　the　stay　areas　from　a　user＇s　mobile　phone　data.　The　proposed　method　can　tackle　the　complicated　situations　that　the　general　method　cannot　deal　with　effectively.　Through　experimental　evaluation,　the　proposed　method　is　shown　to　deliver　excellent　performance.　©　2014　Springer　International　Publishing.