Based on the geometric relationship between the steel rail and the abrasive belt， a calculation model for the grinding depth and profile of the contact area is established to clarify the influence of grinding process parameters on the contact area parameters. As the grinding radius of the abrasive belt increases， the contact area of different steel rail profiles increases logarithmically， and the position of the axis length radius of the contact area changes on different cross-sections. Based on the characteristics of the rail abrasive belt grinding process， a calculation model for heat flux density in the contact area was solved and theoretically verified. Based on the contact area grinding depth and profile calculation， and regional heat flux density calculation model solved above， the instantaneous point heat source temperature field， continuous point heat source temperature field， and continuous action moving point heat source temperature field were applied to discretize the temperature field of the continuous action moving surface heat source in the contact area. Research shows that under the set grinding process parameters， the simulation and theoretical temperature changes on the surface of rail grinding are similar and almost reach the maximum temperature at the same time. The relative error between the simulation and theoretical maximum temperature is 6.14%， which verifies the correctness of the above theoretical model and simulation.