Determining　the　service　regions　of　rail　transit　stations　is　the　precondition　of　rail　traffic　demand　forecasting　and　rail　net　programming.　In　this　paper　individual　travelers　are　studied　instead　of　the　rail　station.　The　utility　of　rail　traffic　station　selection　is　determined　by　the　colligation　of　individual　characters,　travel　characters　and　traffic　service　level.　A　disaggregate　model　of　rail　station　selection　based　on　the　theory　of　the　maximum　travel　utility　is　established.　According　to　the　calculating　result　of　utility,　combining　Reilly＇s　Formula,　attraction　of　the　rail　transit　station　and　the　attraction　intensity　of　the　given　position　around　the　station　are　provided.　Furthermore,　attractive　region　of　rail　stations　in　the　rail　net　are　studied.