Surface coatings are mainly composed of metal oxides(iron oxides, manganese oxides and aluminum oxides etc .), organic materials and little associated minerals according to environmental chemistry. Analytical results indicate that the composition of surface coatings developed in different natural waters differ significantly, with Fe and Al oxides being dominative in the surface coatings, while manganese oxides next to them. It was also found that the content of Fe oxides was much higher than that of Mn oxides. Moreover, there is a significant correlation relationship between contents of metal oxides, organic materials on the surface coatings and those in natural waters.