Vibrating screen sifts materials via screen mesh, vibration displacement and velocity. In order to completing optimal design of vibrating screen’s vibration frequency. Firstly, Using the CAD function of the three dimensional software UG NX 6.0 to achieve vibrating screen modeling. Secondly, modal simulation analysis was carried out using the simulation soft NX NASTRAN. Numerical simulation experimental result indicates: this designed vibrating screen’s natural vibration frequency are 27.79Hz, 32.58 Hz, and 46.39Hz, consequently, designing this vibrating screen should avoid identical or approaching these natural vibration frequencies as far as possible, while choosing the vibration frequency.