This work aims to design two different layers of hairpin winding and simulate the loss of the hairpin winding. With the rise of pure electric and hybrid electric vehicle, hairpin winding motor has been developed and applied rapidly. Because of the high speed of motor, the eddy loss of hairpin winding is especially obvious, which affects the efficiency and temperature rise of motors. In this paper, the basic principle of eddy loss is introduced, and two different layers winding with 4-layer and 8-layer are designed. Through the simulation analysis, it was found that the winding loss of 4-layer winding motor is much larger, and the loss difference between layers is very big. Finally, the 8-layer winding motor scheme is chosen. Therefore, the winding loss of more layers winding decreases at higher speed, but increases at lower speed, and the process cost increases with the number of layers. So the selection of several layers requires simulation,comparison, and comprehensive consideration.