The objective of this paper is to analyse the radial slippage of the ultrasonic motor with double stators and single rotor by the finite element method.Firstly ,the finite element model of the stator is established and the traveling wave motion is applied to the neutral plane of the stator to get the radial displacements of the stator surface particle moving in three dimensional space,which leads to the radial slippage.Secondly,the finite element contact model of the rotor is built and the traveling wave motion is applied to the neutral plane of the stator, the contact status of the stator and the rotor is obtained,verifying the existence of radial slippage.Finally, analyse the effects of different phase on the radial slippage by changing the phase of another stator doing traveling wave motion，the minimum radial slippage is obtained and the phase difference is presenting 180°.The result is identified as being useful in designing and analyzing the ultrasonic motor with two stators and single rotor.
