Abstract: It makes a significant sense to obtain the 3-D information of the building correctly either in martial and civilian field. A method to remove the hidden lines and junctions of perspective drawing was proposed. Firstly, the visibility judgment of each model surface was made using the plane formula and geometry method. Secondly, the boundary line set were generated, which come from the projection calculating to get the perspective drawing and line reconstructing to get the lines needed. Finally, the hide degree inspection according to the relationship between lines and junctions of 3-D wire-frame model were checked, from which the visibility decision of the line was determined. This arithmetic uses the simple data structure to reduce the computational amount. The experimental results show the validity of the model and the effectiveness of the algorithm. The results of performance assessment also provide a new method and supporting means for hidden-removal of the topographic features.