The invention relates to a pressure regulating device on the basis of an air-lift reverse circulation process for cast-in-situ bored piles. The pressure regulating device comprises a pressure regulating device body, a driving drill rod, a faucet, an air compressor and a high-pressure air storage tank, and is characterized in that the pressure regulating device body is connected between the high-pressure air storage tank and the driving drill rod and comprises a pup joint, a ball valve, an air delivery pipe and a connecting plate, the ball valve is connected onto the air delivery pipe, and the upper side and the lower side of the pup joint are respectively fixedly connected with the driving drill rod and the faucet. The pressure regulating device has the advantage that technical problems that a single air compressor in conventional air-lift reverse circulation devices only can control a single air-lift device group, different air-lift devices cannot be simultaneously flexibly regulated and controlled according to actual working conditions and soil layers with different depths, the efficacy of the air compressor cannot be sufficiently utilized, a large quantity of air compressors are required and the like can be solved.