In　order　to　properly　forecast　the　actual　demand　for　parking　place,　the　paper　has　also　introduced　the　main　methods　of　forecasting　the　demand　at　present　time　and　its　characteristics.　Then　it　establishes　the　parking　demand-supply　forecasting　model　based　on　parking　generation　rate　model.　The　model　considers　the　price　and　parking　service　level＇s　impacting　on　the　number　of　parking　demand.　Considering　the　parking　lot＇s　turnover　rate　and　utilization　ratio　in　the　model,　we　can　know　how　much　parking　seats　should　be　built.　At　the　same,　the　demand　for　parking　has　been　respectively　estimated　during　the　different　period　of　daytime　and　nighttime.　At　last,　it　gives　a　calculating　example.