Abstract: Underground balance-type automatic door is in high negative pressure of roadway, and two fans are reverse opening and closing; under the effect of inside and outside pressure difference of air door, the jointed seam is imprecise and air leakage is big, which needs air door chamber during installation. However, depending on electricity as a power for air door in use process is easy to cause accident. Through the analysis, we determine the co-rotating opening and closing model, pneumatic parameter, PLC control system of air door, and select JISI driving cylinder, develop the pneumatic automatic door in the coal mine. The structure of air door is simple without tunneling chamber during installation, and the air door uses underground existing compressed air system control to realize automatic opening and closing, and is safety and energy saving. Practical application shows that two fans of the air door system are opening and closing in the same direction, and the greater of air pressure, the more closely of the air door closing; less fault and convenient maintenance, high safety performance greatly improve the reliability of mine ventilation system.