The plastic-steel sandwich composite board is made of PVC plastic profiled board and colored steel profiled board, and glass wool, rock wool, polystyrene foam and other lightweight, flame-retardant fireproof materials are used as the core material. The layer is a new type of composite building material bonded with polyurethane high-strength adhesive. The product has the characteristics of heat insulation, sound absorption, corrosion resistance and sealing performance, light weight, low cost, fast construction speed, waterproof, heat preservation completed at one time, durability, and beautiful appearance. A single-sided or double-sided outer layer is made through a dedicated composite production line to form a new type of construction and decoration material with high strength, light weight and good thermal insulation effect. Because of its durability, beautiful appearance, convenient construction and low cost, it is widely used in industrial plants, large warehouses, large-span roofs, walls, simple houses, kiosks, cold storage, clean rooms, Air-conditioned rooms and other places