The crowd evacuation simulation in airport terminal is an important method to improve the efficiency of the emergency evacuation decision. Different from traditional pedestrian simulation, the evacuation simulation in airport terminal should fully consider the layout of the terminal building and the characteristics of passenger behavior. This paper proposes a pedestrian behavior model based on potential energy field. On the one hand, the spatial region is modeled by fine grid, so as to model the pedestrian’s body type, pose and decision in airport terminal more realistically; on the other hand, the potential energy field mechanism fully considers following factors’ influence on the pedestrian behavior, including the shortest path to the destination, obstacles, other pedestrians and sudden events. Based on the model, this paper simulates the evacuation process on a certain airport terminal, and evaluates the evacuation ability of the building. Based on the simulation of evacuation time under different number of people and different utilization of building space, the quantitative emergency measures and building optimization recommendations are given. This research can provide advance scientific guidance for pedestrian organization, terminal building design, and emergency plan.