Abstract: The multi-body dynamics simulation software UM was used to establish the vehicle-orbit multi-body dynamics model. Based on the wheel-rail rolling creep theory, the dynamics of the wheel-rail dynamics between the FASTSIM algorithm and the CONTACT algorithm in steady state and transient rolling state were analyzed the difference between forces. The calculation results show that the difference between the horizontal and vertical wheel-rail creeping force and the calculated value of the CONTACT algorithm by the FASTSIM algorithm when the train was traveling in a steady-state rolling state on a linear or curved track was low (10% to 15%).The calculated horizontal and vertical creep force and the calculation value of the CONTACT algorithm were large when driving in transient rolling conditions, especially in the case of large creep, air resistance and other severe working conditions, the difference reached 25%, and with the increase of the speed, the maximum difference reached 30%. It shows that the CONTACT algorithm was more accurate in calculating the creep force under transient rolling conditions than the FASTSIM algorithm, and was more suitable for making safety evaluations on train operation.