The gate rotor was a main part of the single screw compressor. In order to study the vibration characteristics of the gate rotor, wavelet finite element was used to have vibration analysis for it. The Daubechies wavelet plate element was used for meshing depending on transverse deforming theory. The Daubechies wavelet plate element was established by using Daubechies wavelet as shape function, and the finite elment formulation was deduced finally. The top six natural frequencies and mode shapes of the gate rotor were acquired. The results were close to that calculated by ANSYS software. And the correctness of wavelet finite element method was verified. Through calculating the vibration properties of the gate rotor offered the theory instruction for designing and using it.