A kind of finished food boxes stacking machine was designed based on "PC + motion controller". Taking PC as the upper computer and multi axis motion controller as the lower computer, communication between the upper and lower machine used standard Ethernet, HMI and multi axis motion controller communicated via the RS232/485 standard interface, and completed the stacking work via the upper and lower computer. It can realize the function of stacking, reduce the amount of labor, and improve work efficiency. And it provides a new idea for the design of the stacking machine.