With the virtual demonstration development in mobile network, the server side’s computing load becomed the major bottleneck for real-time rendering when facing too much mobile intelligent terminal requests at the same time. In order to resolve this issue ,a real-time LOD simplification method for rendering optimizing was comed. For this method, when server side was working on real time rendering it based on user interaction to render appropriate three-dimensional simplified models, controlled rendering image quantity to avoid unnecessary image rendering and reduced rendering computing load. The level of details models simplify was implemented by GPU parallel processing, through space octree to divide and based on vertex significance level to implement parallel simplification, controlled scene rendering geometry complexity. From experimental results ,this method reduce rendering consumption effectively and guarantee user interaction fluency. In mobile network this method reduce server side loading pressure and improve resource utilization.