Monorail train aerodynamic performance of train through the curve road under different cross-wind conditions was studied and simulation. According to the calculation data, the vehicle body longitudinal, laterally force variation and the train overturning coefficient under the different cross-wind conditions were analyzed. Reference to the relevant assessment criteria for the curve negotiation stability of high-speed trains running, the train speed limit for safe running under the cross-wind velocity 9 was obtained, which provided a basis for security of monorail running under cross-wind effects.