Abstract:The OD matrix is the important data for transit line adjusting and optimizing. The public transportation passenger’s travel behavior was researched based on data from IC cards. A public transportation estimating OD matrix model was presented from the passenger’s boarding and alighting probability and producing and attracting factors of transit site, with the constraints of the boarding and alighting passenger number. The results of a rigorous validation with data from a real bus route reveal that the proposed model is quite effective and reliable.