In order to simplify the modeling and analysis process of the rotor structure,the rotor of a high speed permanent magnet motor was studied,and an equivalent solid rotor model was established by using the method of equivalent mass and stiffness.The modal analysis of the equivalent model was carried out by using ANSYS,and the simulation results were verified by the hammer test.The results show that the error between the first two natural frequencies obtained by the simplified model and the experimental results is less than 5%,and the reliability of this method is verified.The research results provide reference for analyzing rotor modal of high speed permanent magnet motor.