Based on the ANSYS multi field simulation software platform, the fatigue characteristic analysis of the shaft of the high speed induction motor was carried out. The fatigue strength and the reliability of high speed operation of the high speed induction motor shaft are checked. And the life of the motor shaft is predicted. The influence of the electromagnetic force on the fatigue life of the shaft is analyzed. And the type of the fatigue characteristic is judged. The frequency and amplitude of the electromagnetic force acting on the motor structure and the natural frequency of each order of the motor shaft are compared and analyzed. And the strength of the motor shaft is checked. When the shaft does not break due to the electromagnetic vibration, the electromagnetic force is equivalent to the static stress. And the fatigue characteristic of the shaft is analyzed. Whether the motor shaft occurs the short cycle fatigue damage during the life cycle of the motor is checked. The concave fillet design is adopted to further improve the structure reliability of the shaft and the shaft life of the motor.