Abstract: A pressurized air supply apparatus includes an air intake section for sucking air from outside, a compressor which pressurizes and discharges the air sucked by the air intake section, a removing section for removing unnecessary components contained in the pressurized air discharged from the compressor, and a pressure adjusting section with a relief valve for discharging a part of the pressurized air free of unnecessary components for the removing section when the pressure of the pressurized air reaches a value higher than a predetermined value. An output section supplies the pressurized air pressure-adjusted by the pressure adjusting section to a load. An air recycling flow path mixes the pressurized air free of unnecessary components with air from outside. Thus, the apparatus receives the air free of the unnecessary components by air recycling to supply pressurized air of a high degree of cleanliness to the load and, at the same time, to eliminate the air discharge sound from the relief valve.