The modal superposition method was used to obtain the admittance characteristics of damped wheels. Based on the established prediction model of wheel/rail rolling noise and taking the surface roughness of wheels and rails as the excitation, the influence of the position and thickness of a damping layer on vibration and sound radiation characteristics of damped wheels was analyzed. Firstly, a three-dimensional solid finite element model of damped wheels was established, and the Block Lanczos method was used to calculate the modal characteristics of wheels. Secondly, the frequency response function of wheels under unit load was obtained by the modal superposition method. Then, the frequency domain vibration characteristics of wheels under the excitation of roughness spectrum were obtained by the virtual excitation method. Finally, the frequency domain characteristics of acoustic radiation were obtained by an analytic method based on the dynamic responses. The results showed that the damping layer laid on the wheel web has no obvious effect on vibration and noise suppressions of the wheel below 1000Hz, but performs good function above 1600Hz. The noise reduction by the damping layer laid on both sides of the web of the wheel is better than that by the damping layer only laid on one side. The thicker the thickness of the damping layer is, the more obvious the noise reduction is.