Abstract: Accordance with the thickness of the side plates of vibrating screen is redesigned from original 13 mm to 10 mm,MSC Nastran software is used to establish the finite element model for the vibrating screen,and then calculated the natural frequencies and natural modals of the first eight stages of the screen.The result indicates that the side plate with 10 mm thickness is a reliable structure and the work frequency of the vibrating screen avoided the natural frequencies in various stages,which provide necessary theoretical basis for the modification of the screen and indicates that modification design is feasible.