Abstract: The effect of rainfall on high-speed train includes aerodynamic force and impact force of raindrop. Previous studies focused on the effect of rainfall on aerodynamic characteristics of high-speed train. In this paper, based on Marshall-Palmer raindrop size distribution, Euler-Lagrange method is used to establish the aerodynamic model of high-speed train under rainfall environment, and the influence of rainfall on flow field characteristics and aerodynamic characteristics of high-speed train is studied. Based on the energy conservation method, the formula for calculating the impact force of raindrops on the train is derived, and the characteristics of rain load on the train are analyzed. The results show that when the vehicle speed is the same, the longitudinal rain load coefficient, vertical rain load coefficient, aerodynamic drag coefficient and aerodynamic lift coefficient of the head car increase with the increase of rainfall intensity; When the rainfall intensity is the same, the longitudinal rain load coefficient, vertical rain load coefficient, aerodynamic drag coefficient and aerodynamic lift coefficient of the head car decrease with the increase of vehicle speed.