This paper briefly introduces BIM technology and 3D geological modeling and discusses the importance of 3D geological modeling based on BIM technology in geological work, combines the drilling data of a 1∶50000 map of environmental geological survey, aims at the current situation and actual demand of domestic three-dimensional geological modeling based on BIM technology, combines with Lizheng BIM 3D geological modeling technology, the attempt of three-dimensional modeling of 1∶50000 map was carried out. The paper puts forward the application framework of this modeling BIM technology, as well as the method of establishing BIM 3D geological model and the display of results to explore the feasibility of BIM′s guidance for planning and construction in three-dimensional geological modeling.