Abstract: According to the characteristics of large-diameter drill pipe, such as large volume, heavy weight and large quantity used in the drilling process, a large-diameter drill pipe loading and unloading device for coal mine tunnel drilling rig was developed. The paper introduces the scheme formulation of large-diameter drill pipe loading rod device, and describes the design process of manipulator, drill pipe bracket, drill pipe bundle and hoisting unit. In order to improve the efficiency of unloading drill pipe, the rod rubbing device was designed, and the key design points of key components were briefly described. During the industrial test, 3 710 large-diameter drill pipes were unloaded by the large-diameter drill pipe unloading device, with stable action and reliable performance, which met the application requirements of loading and unloading large-diameter drill pipes by tunnel drilling rig.