The selection of appropriate coating materials for internal and external anti-corrosion coated composite steel pipes is crucial to ensure the adhesion strength of the internal and external coatings. The internal and external anti-corrosion coated composite steel pipe coating material should have high adhesion and corrosion resistance to ensure effective adhesion to the surface of the steel pipe and not easily corroded by the external environment. Common coating materials for internal and external anti-corrosion coated composite steel pipes include epoxy resin, polyethylene, and polypropylene.