In order to explore the impact of altitude on the emergency evacuation of aircraft passengers at airports, a simulation model for emergency evacuation of aircraft accidents at airports was built. By introducing panic factor, age factor, gender factor and altitude correction factor, passenger walking speed at different altitudes was quantitatively characterized, and passenger evacuation effects were analyzed under conditions such as different altitudes, with or without evacuation guidance, and cabin aisle spacing, dual aircraft evacuation. The results show that the impact of emergency evacuation time in a high plateau environment is mainly reflected in the middle and late stages of cabin evacuation and ground evacuation. When the altitude is 4 280 m, the cabin evacuation time is increased by 19.6 s and the overall evacuation time is increased by 44.1 s compared with the plain area. By setting cabin crew guidance, cabin evacuation time is reduced by 18.1 s and evacuation efficiency is increased by 16.5%. When the width of aisle spacing is increased to 60 cm, the evacuation time in the cabin is reduced by 20.8 s, and the evacuation efficiency is increased by 19%. Compared with single-aircraft evacuation, the evacuation time of dual-aircraft evacuation is significantly increased, so it is necessary to optimize the evacuation strategy. The research results can provide theoretical support for the optimization of aircraft emergency evacuation schemes at high plateau airport.