Abstract: Rational development and utilization of urban underground space is of great significance for improving urban environment, building livable cities and enhancing urban comprehensive carrying capacity. 3D geological modeling is the most commonly used technology to directly reflect the geological conditions below the surface, which is widely used in the development and utilization planning of underground space. The fifth national new district "Lanzhou New Area" is located in the Qin Wang Chuan Basin, and its development and utilization of the underground space must be based on a full understanding of the geological conditions. In this paper, the engineering geological drilling data was used as the data of 3D geological modeling. The 3D geological model of the Qin Wang Chuan Basin was established by using GMS software, and the surface elevation was modified by using DEM data. By comparison, it is found that the modified model is closer to the real situation on the surface, and overcomes the model distortion caused by the interpolation of the borehole elevation. The model shows the geomorphological features and strata spatial distribution of the Qin Wang Chuan Basin, which has a certain reference value for the underground space planning and construction of Lanzhou New Area.