An air-liquid pressure conversion control device. The device uses a combination of a large-diameter air cylinder and a small-diameter hydraulic cylinder, and drives a piston of the hydraulic cylinder to reciprocate by utilizing the push-pull reciprocating movement of the air cylinder, so as to complete oil suction and oil output functions of the device. A pneumatic control valve (10) is further disclosed. Air intake is controlled by the pneumatic control valve and then a piston rod (8) is pushed to move, oil cylinders are controlled to output oil alternately to provide pressure, and the oil output pressure of a hydraulic system composed of the oil cylinders is controlled by regulating an air intake pressure by the pneumatic control valve. A hydraulic energy accumulator buffers pressure pulsation, caused by discontinuous oil supply occurring at the reversing moment of the air cylinder, of the air-liquid pressure conversion control device. Moving components such as the piston of the device are made of aluminum alloy materials. The weight of reciprocating movement components is reduced as much as possible while the strength is ensured, the reversing sensitivity is improved, and the pressure pulsation is also reduced while the energy consumption of reversing is reduced.