Abstract: This paper presents the basic functions of visualization design system for lightning rod protecting area calculation, including 3D display of protecting area, generation of engineering drawings by elevation views, design of lightning rod parameters such as height, quantity, location, etc. The overall structure of this system and the relationships of data transfer between modules are designed. And by means of VC+KG-*3+ and OpenGL, 3D visualization of the protecting curve surface, to the lightning rod type with single needle, two or three needles in various heights has been implemented.