The drum surface method was proposed to fit the dual curvature glass. The drum surface was obtained from the automotive body cloudy data with the motion equation by using line element geometry and KLocalRANSAC algorithm. Based on the drum line principle, the proportional function method was used to obtain the guide rail curve. At the same time, the motion deviation was analyzed and the max motion deviation was not more than 0.6 mm. The results fully achieve the engineering requirements. It is proved that the drum surface fitting method and the guide rail design are correct and reasonable.