Abstract: the investigation on rail corrugation formation due to the wheel stick-slip process on curved tracks, and on consequential track impact response, using a nonlinear vehicle-track model are presented in this paper. The vehicle was described using up to 78 degrees of freedom (Dofs). The track is considered as two rails discretely supported by viscous-elastic elements. Simulations show that the frequency of wheel stick-slip process is composed of a basic frequency, which matches the sleeper passing frequency and a second frequency that corresponds to the combined torsional and bending frequency of the wheelset. It was found that the wheel stick-slip process on the high rail oscillates at the basic frequency while the dominant frequency on the low rail is double basic frequency. The effects of some important parameters - the wheel-rail friction characteristics, the wheel-rail profiles and the vehicle speed, etc. on wheel stick-slip process were also investigated.