Abstract: With the accelerated process of urbanization in China,urban development is facing increasingly complex spatial relations and spatial decision,in particular the project's planning decisions continue to affect the coordination of the city's environment,based on 2D floor plan and rendering of planning decisions already cannot satisfy urban management needs.According to 3D GIS,the technical methods of real 3D environment and virtual planning model combining is put forward,a variety of 3D spatial analysis technique is studied,the system is developed and put into practical application of engineering.