In order to study the key factors of aerodynamic noise simulation of the metro traction motor and improve the simulation accuracy of aerodynamic noise,simulation comparison and analysis are performed with a self-ventilated metro traction motor as an example using ACTRAN software. The factors considered include the acoustic mesh size, the interpolation order of noise radiation from source region to the infinite field, and the properties of air medium under local temperature and humidity conditions.Then the simulation results are compared with the experiment results, which verifies the influence of key factors on the precision and efficiency of aerodynamic noise and provides a basis for more accurate and efficient simulation calculation of traction motor noise.