Abstract: In view of the problems of single function, non intuitive display and unable to guide drilling construction of trajectory while drilling and hand-held trajectory measurement software for rotary drilling in coal mine, the drilling data processing software is developed with C# language. The software has four functional modules: data preprocessing, drilling depth and drilling trajectory calculation, 3D modeling and display of drilling trajectory and subsequent guide for drilling trajectory design. It can realize the import and processing of drilling data, visual display of drilling depth and drilling trajectory, quantitative calculation of blind area covered by drilling and guidance of subsequent drilling construction. By using the software, the trajectory of drilling group and the final point can be quickly located, and the blind area and the relationship between drilling and coal seam can be accurately determined. The field test shows that the drilling data processing and 3D display software are reliable and stable, the data processing is simple and effective, and the 3D display of drilling group trajectory and coal seam distribution is intuitive and clear, which can provide timely and effective technical support for subsequent drilling construction.