Abstract: In view of problems of difficulties and security risks in operation of loading and unloading of drilling pipe caused by high hole position and large hole opening angle in current coal mine tunnel drilling construction, a mine-used drilling pipe replacing device and its control system were designed. The drilling pipe replacing device is used with active drilling pipe of power head of drilling rig and the hold, to achieve loading and unloading of drilling pipe in the middle. The control system takes mine intrinsically safe and flameproof hydraulic controller as the core, and drives control proportional solenoid valve and commutation solenoid valve by PWM signal and switching signal respectively, so as to adjust the expansion and contraction speed of the cylinder. The cylinder telescopic length signal driven by proportional solenoid valve is fed back to controller by magnetostrictive sensor to form closed-loop control of the cylinder telescopic position. The test results show that the mine-used drilling pipe replacing device for drilling rig can match the existing type of drilling rig, and meet the needs of automatic loading and unloading of drilling pipe in the large-height or large-angle sidetrack drilling construction, thus improves the drilling construction efficiency and the safety of the drilling pipe replacing operation.