The wood plastic sheet extrusion line has the advantages of compact structure, good plasticizing effect, high yield and good durability. The unit uses a specially designed conical twin screw extruder, the use of imported frequency converter speed, the use of imported RKC temperature control instrument, with a wide range of adjustment, high temperature control precision, easy to operate and reliable advantages. The auxiliary machine is composed of vacuum shaping table, traction machine, cutting machine and material pushing frame. Equipped with large cooling device to ensure the door plank shaping effect. The caterpillar tractor adopts imported reducer motor and frequency converter, which has the advantages of reasonable structure, large traction force, stable traction and so on. The cutting machine has the advantages of reliable and accurate operation, high cutting precision, and the pushing rack is provided with a movable pushing trolley and a special rubber protective layer. The auxiliary unit adopts programmable computer control or domestic famous brand control system.