Abstract: The paper conducts an investigation of the typical choice behavior for the unbalanced operation of Park and Ride in Shanghai .According to the results of the preliminary investigation ,travel time is the most important impact factor and the second most important impact factor is the travel cost .In order to verify the universality of the conclusion , this paper investigated the travel costs of typical travel routes at the peak time by network observation supplemented by actual travel time data .The study finds that :(1) P+R facilities in Shanghai can be divided into urban and suburban lots , and many users are derived from the public transportation and other motorized travel modes ;(2) drivers value travel time the most ,whose time value is higher in traffic jams than in free-flow road conditions ;(3) public transportation passen-gers are abstracted by the travel time savings while taxi users tempted by the travel cost ;(4) P+ R can promote multi-model travel mode ,and residents with imperfect bus transit services have higher demand for P+R facilities .