Abstract: Temperature rise and thermal stress due to wheel/rail friction play an important role in the failure of wear,flatting and checking.A thermal-mechanical coupling contact model of wheel/rail in sliding contact was put forward to calculate the temperature rise and thermal stress with finite element method.The non-steady heat conduction between the contacting surfaces of the wheel/rail,heat-convection and radiation between the wheel/rail and an ambient were taken into consideration.The contact pressure distribution was obtained by contact element method.The thermal effects only exist in the thin layer of wheel/rail,and its offect decreased as depth increased.Higher sliding speed leads to stronger thermal effects.