The invention relates to automatic machining equipment used for corrugated paper packaging boxes and provided with changeable multi-shape tool bits. The equipment comprises a bottom plate; a changeable cut device is mounted in the middle of the upper end surface of the bottom plate through screws and can realize the quick switching function for die-cutting tool bits, the die-cutting speed for the packaging boxes is greatly increased, and the working efficiency is improved; two conveying devices are symmetrically mounted on two sides of the upper end surface of the bottom plate and can realize the effect of automatically conveying the die-cut packaging boxes; and two connection branch chains are mounted between the changeable cut device and the two conveying devices and can guarantee that the packaging boxes conveyed by the conveying devices can smoothly enter the changeable cut device for operation. With the equipment, the rapid die-cutting function for the corrugated paper packaging boxes can be realized under rapid changing of the die-cutting tool bits, the time for changing the tool bits is greatly shortened, and the equipment has the advantages of being convenient to operate, simple in process steps, high in working efficiency and the like.