Abstract: Permanent magnet synchronous motors(PMSMs) have attracted much attention in the field of new energy electric vehicles due to their high power density and high efficiency. The optimization design and performance analysis of permanent magnet motor for electric vehicle are carried out by using the advantages of high slot full rate and good heat dissipation performance of flat wire winding. Firstly, based on the 8-pole 48-slot flat-wire permanent magnet motor model, the influence of stator-side structural parameters on motor torque and torque ripple is analyzed. Secondly, the method of opening auxiliary slots on the rotor surface is used to optimize the torque output of the motor. Taking the average torque and torque ripple as the optimization objectives, the structural parameters of the auxiliary slots are scanned by single variable, and the range of optimization variables is determined. The optimization method combining the response surface model and the NSGA-II algorithm is used to optimize the multi-objective optimization of the motor. Finally, the electromagnetic characteristics of the motor under no-load and multi-load operation are analyzed, and the efficiency map of the motor is obtained. The results show that the maximum efficiency of the motor is 96.63%, and the proportion of efficient operation area with efficiency greater than 85% reaches 91.36%, which meets the requirements of the electric vehicle drive motor, and provides a reference for the design and characteristic research of this kind of motor.