Abstract: In order to solve the problems of shifting impact, hard operation, easy abrasion and inconvenient maintenance of the manual mechanical shifting system which is used by the mining hydraulic transmission diesel engine vehicle at present. The author developed a Semi-automatic electro hydraulic transmission control system suitable for the characteristics and working conditions of underground. This paper describes the principle of the system, the design of the hydraulic control part, and the performance test of the system. The research and development of this system has a good guiding significance and application value to improve the driving comfort, improve the life of the transmission system, and facilitate the maintenance of vehicles.