Abstract: An air control switch set for a switching machine, including a base frame, an air control valve fixedly mounted on the base frame to guide air from an air source to an air nozzle and thread suction device, a switch controlled to close/open the air control valve, a control bar vertically slidably coupled to the base frame and reciprocated by a pedal, a pull rod having a bottom end fixedly fastened to the base frame and a top end coupled to a motor through a link, a stop member fixedly mounted on the control bar, and a rocker arm turned about a pivot at the base frame and forced by the stop member to press on the switch in opening the air control valve upon a down stroke of the control bar before the base frame is lowered with the control bar to move the link in turning on the motor.