Sponge foaming box

The utility model belongs to the technical field of foaming boxes, and discloses a sponge foaming box which comprises a bottom plate, a first side plate, a back plate and a second side plate are fixedly installed on the upper surface of the bottom plate, and a sliding groove is formed in the upper surface of the bottom plate; and the movable plate is connected to the upper end of the sliding groove in a sliding mode, a second sealing door is hinged to one side of the movable plate, and output shafts of the two electric push rods are rotationally connected to the left side and the right side of the cover plate respectively. The movable plate, the back plate, the first side plate and the first sealing door are combined to form foaming boxes of different sizes, sponge foaming is put into the combined foaming boxes, the cover plate covers the foaming boxes through the electric push rod, and therefore the foaming boxes can produce sponges of different sizes, and after sponge production is completed, the cover plat