To explore the law of damage and degradation of anti-corrosion coatings on steel components of inland ports under water-sand erosion conditions，experimental research is conducted on the damage and degradation of coating materials under different erosion conditions using a self-made water-sand accelerated erosion wear device.Based on image recognition technology，digital and binary feature extraction is carried out to hedge the surface topography of coatings after corrosion damage.The gray threshold of distinguishing pixel pores is set to quantitatively analyze the damage form and degradation area of the coating surface.The results show that when the inflow angle is 45°，the damage and deterioration of the coating are the most serious，and the pitting ratio and scratch ratio are roughly the same.The damage and deterioration area of the coating increases exponentially with the increase of the inflow velocity.When the sand content is less than 45 kg/m3，the increase of the sand content can promote the damage and deterioration of the coating，but when it is more than 45 kg/m3，it reduces the damage and deterioration rate of the coating，which realizes the damage and deterioration law analysis of the steel component coating under the erosion condition of inland river and sand without damage.