The 3D solid modeling technology is the basic of the virtual model in the virtual reality, as well as is the core element of the CAD system. It has quickly become the mainstream of theCAD technology. Computational geometry is to use the computer to transform, synthesize and analyze the physical geometry information. The 3D modeling technology can be divided into the following three types: (1) point-line modeling technology (2) plane modeling technology (3) 3D solid modeling technology.