Abstract: The influencing factors of energy-saving and drag-reducing of inner-coated steel pipe were analyzed, the drag-reducing effect of wall surface was calculated from practical application cases, and the application performance of the coated steel pipe was evaluated.The results show that the inner surface roughness of high-temperature-resistant and corrosion-resistant steel pipe is obviously reduced, and the effect of energy-saving and drag-reducing of the coated steel pipe is obvious.