Abstract: With the advantages of intuitive image, simple operation and rich function, the visualization technology of 3D geological model is widely used in geology, minerals, engineering and other fields. After summarizing the features of surface modeling and voxel modeling method, this paper explores the implementation on IDL platform by developing application. In addition, the simulation ability of dynamic processes, which is suitable for displaying landslide, debris flow, land subsidence and the like was achieved. Finally, the model construction and visualization of a coal field and debris flow were taken as examples to verify the effectiveness. Through testing, IDL can complete 3D geological modeling task well, and shows its own advantages in interpolation and segmentation, which provides a way for the realization of engineering geological information.