For the gradual throttling hydraulic buffer ideal buffering characteristics, a modeling method was put forward that based on a kind of ideal buffer processing of throttle lever external contour curve. The method was based on the analysis of buffer mechanism of the gradual hydraulic buffer. The damping hole on both sides of the flow equation was established, the external dimensions equation of the throttle lever was deduced and the outline of the throttle lever curve was drawn using the MATLAB numerical analysis method. The contour curve obtained was applied in the actual process of buffering, by the analysis of buffer characteristic curve obtained, the feasibility of the modeling method was validated, and the collision of different impact load condition were compared. The results show that buffer obtained through this kind of modeling method can achieve ideal buffer properties and can absorbed impact energy less than the rating safely.