Abstract: The types of external coating of buried steel pipelines and coatings' application home and abroad are introduced.In the light of shortcomings of various coatings in practical use, a new coating material—100% solid polyurethane coating material (2K or DD type) is recommended to use.This kind of coating material has advantages in comprehensive properties, strong suitability, filming with one-time's spraying, painting and casting, and formed coating covers from elastomer to rigidity with perfect properties in anti-corrosion and mechanical strength.