Abstract: This article is based on a refined train-tunnel coupling turbulence model to simulate and analyze the pressure waves in the central constant velocity intersection of high-speed trains at a speed of 400 km/h.By combining the wave trajectory diagram, the flow field characteristics inside the tunnel and the pressure history characteristics at different measurement points inside the train and tunnel are analyzed.Based on the simulation analysis of 400 km/h high-speed train tunnel intersection, the aerodynamic force and numerical characteristics of 400 km/h high-speed trains were first proposed, the average and maximum values of aerodynamic resistance, aerodynamic lift, and aerodynamic lateral force of the entire vehicle and different areas during the train intersection process were analyzed, especially the phenomenon of "negative lift" generated by the head car under train tunnel conditions, which was analyzed in combination with the calculation results.The results show that the peak pressure of the entire vehicle under the condition of intersection in the 400 km/h high-speed train tunnel is about 12 kPa, and the peak pressure of the aerodynamic load in the middle of the tunnel is about 15.5 kPa.The head car has the most significant negative lift effect on the entire vehicle, with a maximum negative lift of 14.7 kN in the head area and an average negative lift of 8.71 kN.