The separating behavior is crowd movements from single flow divide into two distributary-flows because of different pedestrian moving target. In the current research system of pedestrian flow simulation, there is a lack of simulation research on separating crowd behavior in T-shaped channel. By conducting a series of controlled experiments, we analyzed the moving trajectory and the spatial and temporal distribution characteristics of pedestrians in separation process. Based on the analysis results of the controlled experiment, we proposed an improved social force model, which fully considered the characteristics of pedestrians’ swapping location and refined the direction of pedestrians’ expected speed in three stages of pedestrian separation process. In the simulation, we applied the improved model to explore the effect of pedestrians’ swapping location on the macroscopic phenomena, microscopic individual behavior and the traffic efficiency of T-shaped channel. The simulation results show that if pedestrians’ swapping locations are concentrated in a certain area that close to entrance, the traffic efficiency of T-shaped channel will be higher than that pedestrians’ swapping locations are dispersed. And as the flow rate of entrance increases, the closer concentrated swapping location is to the entrance, the higher the mean speed and the fewer the conflicts between pedestrians.