The improvement of milling processing efficiency and machining accuracy will require the improvement of milling machine processing speed. With the development of magnetic levitation technology, highspeed magnetic levitation electric spindle has become a key component of milling machine. The magnetic levitating motorized spindle rotor system has strong gyro coupling effect at high speed operation, and its excessive coupling effect makes the stability region of high speed milling narrow and even makes the milling system unstable. So, a control method based on PD controller for modal decoupling-state feedback was proposed. By using the method, the coupling between the translational mode and the rotational mode of the rotor system and the coupling between the rotational modes in the two directions were decoupled,the proportional and damping coefficients of the controller were independently adjusted to reduce the influence of the gyro coupling effect on the stability region of the magnetic levitation milling system, and the stability region of milling was improved. The effects of modal decoupling-state feedback control gyro coupling effects on the stability of the milling region based on PD controller were studied by simulation. The results show that by using the modal decoupling-state feedback control technology based on PD controller, not only the effect of gyro effect on milling stability type can be reduced, but also the stability area of milling can be improved.