Abstract: Based on the basic principles of determining mine surface movement scope by rock movement angle, an auto-generating method using CAD was proposed, with the following steps:find out the intersection points of the ground surface with the mine movement boundary according to rock movement angles in the geological sectional drawing; determine firstly the coordinates of the deepest point (or the most prominent point) X (or Y) and Z in the selected geological sectional drawing, then to project that point to the surface topographic drawing, furthermore the mine movement scope boundary point is determined through mathematic drawing method on considering the contour line and the profile intersect at one point; the mine movement scope is finally formed by connecting all the boundary points together.