A set of experimental schemes of pedestrian evacuation from a room having two exits is proposed and applied to experiments. Some quantitative results of evacuation time varying with the number of pedestrians in different circumstances are obtained from the video recordings. The concept of attraction domain of a two-exit room is established. It is proved that the boundary curve of attraction domain of the smaller exit is always a circular arch, by which the mechanism of arch formation near an exit can be illustrated. Compared with the passenger evacuation procedure in a subway waiting hall, we have established a quadratic function model of evacuation time which can fit the measured data well for various cases. The evacuation time increases linearly with the number of people without waiting, and increases as a quadratic function of the number of people after the formation of a waiting region. It is also found that the expression is affected by the width of exit more sensitively than in other well-known models.