Abstract: This paper introduces a semi-automatic drilling machine pneumatic system and PLC control system. The main content is the composition and action sequence of the semi-automatic drilling machine pneumatic system. Based on Fluidsim P software, the relay control circuit and PLC wiring diagram are designed, and the simulation operation is carried out. The control program of Siemens S7-200PLC is made, and the interface of touch screen control panel is designed by MCGS.