▎ 摘　　要

NOVELTY - The method comprises: (A) subjecting base material to vortex flaw detection; after straightening, removing rust; where the base material is steel material; (B) soaking the base material into zinc liquid which is melted at 400-600 degrees C to make the zinc layer adhere to the base material surface; (C) cooling the base material after the hot-dip zinc treatment, and then performing passivation and degreasing treatment; (D) immersing the base material into zinc phosphating solution after cleaning to form phosphating film; (E) cleaning the substrate after phosphating treatment, drying and then spraying zinc-rich primer, after curing, spraying the external decorative coating, then curing to obtain the semi-finished product; and (F) preparing the semi-finished product into the guardrail. USE - The method is useful for preparing guardrail with good corrosion resistance. ADVANTAGE - The method effectively improves the anti-corrosion ability of the guardrail base material, so that the prepared guardrail has excellent corrosion resistance effect.