In order to explore the dynamics performance of WN (Wildhaber-Novikov) gear transmission, according to the WN gear meshing transmission principle and the forced vibration theory with multi-mass and multi-degree of freedom, the nonlinear two degree of freedom forced vibration analysis model of WN gear pairs load meshing was established. Using vibration analysis and experiment, the meshing vibration behavior and tooth root bend strength of WN Gear were synthetically researched. The example calculation and the solution of the motion differential equations were completed by using numerical analysis method. The application foundation is improved for the dynamics design of WN gear transmission.