The utility model discloses a biodegradable plastic bag punching machine, comprising a base, wherein the top two ends of the base are fixedly connected with vertical plates, the top of the two vertical plates is fixedly connected with a horizontal plate, the bottom of the horizontal plate is provided with a punching device, a砧板 is rotatably connected between the vertical plates, the center of the砧板 is provided with a circular groove, a rotating device is provided in the circular groove, one side of the砧板 is provided with a card slot, and one side of the砧板 is provided with a料盒. The utility model can reduce the damage speed of the冲料板 and save cost by setting the worm to drive the worm wheel to rotate, and then drive the冲料板 to rotate, so that the punching knife falls on different positions of the冲料板 each time the punching is performed. The electric push rod can drive the砧板 to rotate at a certain angle, so that the砧板 tilts toward the料盒, which is convenient for concentrating the waste materials into the料盒 after the punching is completed, and is convenient for cleaning and quickly performing the next punching. The rubber垫片 can be used to fix the plastic bag to be punched.