The invention discloses a high-differential pressure air blower device. The high-differential pressure air blower device comprises a shell with an inlet and an outlet, and an impeller assembly capable of making airflow move in the shell in a directional mode is arranged in the shell; the impeller assembly comprises a supporting shaft and a fixing ring, a fan blade is arranged between the supporting shaft and fixing ring, and the impeller assembly is installed on the shell through matching between a bearing and the supporting shaft. According to the air blower device, an inner bush of the bearing and the supporting shaft are designed in an integrated mode; an arc-shaped contact face is adopted, in this way, the leakage route of gas is lengthened, the section area of a gas leakage face is reduced, full sealing of the supporting shaft is achieved, and the problem that gas in an inner cavity of the air blower device leaks from the bearing is solved; conditions are created for increase of air pressure, and the air blower device is simple in structure and easy to assemble and increases the air pressure.