Abstract: The AutoCAD drawing software is widely used in many fields, however, it is so difficult for the basic functions of the AutoCAD drawing software to meet the drawing requirements under the actual conditions of some complex CAD questions or the professional design works.In the practical work, the spatial relationships of the coal mine tunnel plan is obtained not easily by manual processing method, and the same time, the workload is so huge. To deal with this questions, a set of automatic processing software is designed to gain the spatial relationships of roadway. Some related researched results proved that, the newly design software is goof for the work efficiency and technical level of the mine drawing workers. Moreover,this research results also conducive to the development of computeraided design.

Key words: Spatial relationships of the roadway, Secondary development of CAD, Curve interrupted