Abstract: 3D real scene should meet the needs of managing natural resources, society and economics, which puts forward making basic geographic information products entitize. The simplification of 3D model is the key link of the transformation. Based on the experience of existing methods, this paper proposes a simplification method for 3D model based on CityGML. Based on two-dimensional vector of the solid profile of the figure vertex coordinates and elevation information, build polygons for walls, roof, etc. Combine the polygons into a simple three-dimensional expression. Then Texture map with Render to Texture technology (RTT), build 3D model for each two-dimensional vector by refactoring semantics and LOD levels based on CityGML. This method can successfully make 3D model entitize which occupies a small capacity, and meets various application demands of 3D real scene.

Key words: new fundamental surveying and mapping, geo-entity, 3D real scene, simplification, CityGML