More passengers would be able to be transported to their destinations when boarding and alighting time of subways in rush hours is reduced and the efficiency of the system will be increased as well.Currently,most of the stud-ies on boarding and alighting behaviors of passengers are carried out based on the hypothesis that all the passengers on a train would get off,which is not the case for most boarding/alighting stations.In the present study,the scenario that only a part of passengers get off the train is investigated through a social force model.In combination with a waiting model,the remaining passengers are assumed to stay at their original position.The proportion and distributions of alighting passen-gers,ratio of boarding/alighting passengers as well as the influence of door width on the boarding/alighting time are sim-ulated and analyzed.The results show that boarding/alighting time of passengers decreases by 39.62% and 39.7% at most respectively when door width increases by 23.08%.With an increase of the ratio of boarding/alighting passengers,the av-erage boarding time tend to decrease while alighting time increases.Alighting time can be reduced to 72.16% when the lo-cations of alighting passengers are optimized.