AIR SUSPENSION SYSTEM

An air suspension system includes: an air suspension interposed between a vehicle body and an axle to adjust a vehicle height according to supply and exhaust of air; a compressor that compresses air; a tank that stores the air compressed by the compressor; and an air dryer provided on an ejection side of the compressor. When the tank has a predetermined pressure or less after air is supplied from the tank to the air suspension, a pressure of the tank is increased by the compressor.