Based on the Taguchi's orthogonal design experiment, taking the maximum temperature of the stator winding as the experimental index, the influence of the parameters of the cooling ribs on the heat dissipation performance of the motor is analyzed by the numerical simulation. Through the range analysis, it is found that the order of the factors affecting the maximum temperature of the stator winding is， the height of the cooling ribs, the spacing of the cooling ribs, and the width of the cooling ribs. Considering the material cost and the weight reduction requirements of the motor, the best level combination is obtained as the height of the cooling rib is 30 mm, the width of the cooling rib is 4 mm, and the spacing of the cooling rib is 20 mm.