Abstract: Erosion-resisting characteristics of C25,C35 and C50 concretes were tested in an environment of freezing and thawing cycle. The result showed that the corrosion became more and more serious successively under clear water,the solution of sodium sulfate,and the solution of sodium sulfate with sodium chloride after 300 times of freezing-thawing actions. The damage to a concrete specimen was gradually serious with a decrease in concrete strength and a gradual increase in water cement ratio. The concrete samples protected by SPUA were in good condition. The main problem was spalling from surface to interior which appeared different tendency with different salt solution.