For vibration and noise reduction of the most railway wheels, corresponding dampers are generally installed to increase the structural damping of wheels, so as to reduce vibration and noise. Wheel-damper system was a wheel system with multilayer damper installed. The dynamic model of wheel-damper system of railway vehicle was established, and the equivalent ratio model of wheel-damper system was derived. A method for obtaining the modal damping ratio of structures based on theoretical model and simulation and independent of modal test was presented. Combined with abaqus modal superposition method, the vibration frequency response function(FRF) of the wheel-damper system was calculated. Finally, the vibration frequency response function of the wheel-damper system was tested, and the simulation results are in good agreement with the text results, which shows that the method is an important means to qualitatively compare the damping performance of different wheel damper devices in the design stage.