Abstract: In order to enhance the directional display of coal mine geology and achieve visual display and auxiliary data analysis of underground drilling groups in coal mines, this paper discusses the main steps of 3D visualization of directional drilling group trajectory, and expounds the core methods and key technologies in each step. The 3D visualization software of directional drilling group trajectory is designed and its main functions, data flow and logic block diagram are shown. The corresponding software is developed based on C# and WPF programming and part of the 3D visualization effect is shown.