Abstract: In order to improve the torque performance and suspension performance of the interior bearingless permanent magnet synchronous motor (IBPMSM), an IBPMSM multi-objective optimization design method based on the response surface method and multi-objective particle swarm optimization (MOPSO) algorithm is proposed. Firstly, the principle of suspension force generation of the IBPMSM is introduced. Secondly, the principles of response surface method and MOPSO algorithm used in the proposed optimization design method are clarified. Thirdly, according to the proposed multi-objective optimization design method, an IBPMSM is optimized by the steps of sensitivity analysis, response surface method modeling and MOPSO. The torque performance and suspension performance of the optimal motor and the initial motor are compared and analyzed. Finally, an optimal design prototype motor is manufactured, and an experimental platform is built to test the performance of the prototype motor.