With the modernization of the society and improvement of technologies, people have new requirement for the communication mode between human and computer. And it leads to the appearance of Virtual Reality technology. The Virtual Reality technology is an integration of computer graphics technique, multi media technique, sensor technique, display techniques, simulation technique, and Internet technologies and so on. It builds virtual scenes on the network to implement a platform that multi-users from different places can immerse into and communicate with each other with no bound.