Abstract: It is significant to improve the hydraulic system for better performance of drilling rig and the higher ratio of finishing gas hole.The current state of the development of hydraulic system drilling rig in tunnel is discussed from the perspective of the drilling process and energy saving.The hydraulic system of ZDY6000L track-mounted drilling rig is developed,and rotational,feeding and assistant loops are described.The experiment of ZDY6000L drilling rig showed that the developed hydraulic system is of high effectiveness and reliability,as well as fine flexibility and energy saving.