In this paper, the high-frequency vibrations of (yxl)58°LiNbO3lateral electric fields(LFE) resonators are studied. Firstly, based on Mindlin’s first-order plate theory, the modal spectrum relationship of piezoelectric resonator is calculated, and the lengththickness ratio of crystal substrate is obtained. Then, the threedimensional finite element model of the resonator is established by using the finite element analysis software COMSOL Multiphysics. By increasing the thickness direction grid to sweep the layer number, the gridindependence of the simulation model is verified. Besides, the characteristic frequency calculation and frequency domain calculation are carried out to obtain the firstorder thicknessshear mode vibrations frequency value. Finally, by changing the mass ratio of the electrode to the crystal plate and the size of the electrode spacing, the influence of different size parameters on the highfrequency vibration characteristics of the resonator is obtained.