The coating of 3PE anti-corrosion steel pipe is an epoxy powder anti-corrosion coating that contacts the bottom layer and the surface of the steel pipe. The middle layer of 3PE anti-corrosion steel pipe is a copolymer adhesive with branching functional groups, and the surface layer is a high-density polyethylene anti-corrosion coating. Therefore, the 3PE anti-corrosion coating combines the high impermeability and high mechanical properties of epoxy resin and polyethylene materials.