The so-called coating is actually a system engineering, which is a material protection technology that uses paint to form an organic coating on the surface of the protected object. The process involved in painting includes three basic processes: treatment of the surface of the object to be coated before painting, coating process and drying, and selection of suitable paint. Coating is a key procedure in the surface manufacturing process of construction machinery products, and the appearance quality of the product directly reflects product protection, decorative performance, and product value. This article introduces how to carry out quality control in the production stage of the coating coating system.