Abstract: The process design and parameter debugging of automatic following machine for fully mechanized mining are costly, time-consuming and cumbersome. In order to solve the above problems, the digital twin system architecture of following process for fully mechanized mining is proposed. The study analyzes the aspects of physical equipment, virtual and real interaction, twin data, mechanism model, simulation algorithm and process application. The key technologies such as the transmission and storage of the following process data, the playback of the following process history, the real-time following process twin deduction, the rehearsal simulation of following process, and the instruction scheduling of following process are described in detail. The paper puts forward the technical roadmap of the digital twin system of following process for fully mechanized machining. Through 10 Gigabit optical fiber ring network+5G communication, the shearer process action data is collected to the shearer host. The support process action data sent by the serial support controller is collected to the electrohydraulic control host. The process data is collected, classified and coded according to the action sequence as the data source for the playback of the process. At the same time, the host computer forwards the real-time reported following process data to the 3D digital twin system. The twin system deduces the following process in the 3D virtual scene. After the following process parameters are configured on the human-computer interface, the following process for fully mechanized mining can be previewed in the 3D scene. During the real-time mining process, the system will collect all kinds of sensor data and issue process scheduling instructions in combination with the rehearsal of error-free following process. The support controller is changed from a decision-maker to an executor to overcome the limitation of the limited computing power of the controller due to the lack of underground space. The field application results show that the digital twin system can provide technical reference for the process design, parameter configuration and simulation test of following process for fully mechanized mining. The system can shorten the development cycle of the following process from 14 days to 1 day, making the modification of the following process design more convenient. The system improves the following automation rate in working face to more than 90%.