Abstract:The series composed by two-dimension beam mode function is used to approximate the transverse displacement function of visco-elastic cantilevered plate, and the transverse deformation of the plate on which a concentrated force is acted is calculated by using Ritz’s method. By solving Lagrange’s equation, the frequencies and model loss factors of free vibration of the plate are obtained, then transient response of visco-elastic cantilevered plate, when the concentrated force is withdrew suddenly, is obtained by using the method of mode superposition. Also the effects of loss factor, module and thickness of viscoelastic layer on the response are analyzed.