An automatic cutting machine comprises a chassis, a frame, a main motor, a protective cover and a blade. The blade is driven by the main motor and is integrated with the main motor and the protective cover. The chassis is provided with a feed screw vertical to the chassis, a feed sliding plate which can move up and down along with rotation of the feed screw is arranged on the feed screw, the main motor is fixed on the feed sliding plate, the feed screw is driven by a feed motor arranged on the frame, the feed motor adjusts the rotation speed and the rotation direction by an automatic control unit, and further controls the feed speed, the down cut and the reset of the cutting machine based on the rotation speed and the rotation direction. By virtue of an automatic feed cutting mode, the cutting machine can help reduce the labor intensity of workers, prolong the service life of the motors, improve the machining precision and safety performance of the cutting machine, and improve the processing precision and safety performance.