Abstract: In this paper, aiming at the problem of sediment transport characteristics of granite small watershed in South China, taking Wushui watershed in Hengyang County, Hunan Province as the research object, the Mann-Kendall catastrophe analysis method, double cumulative curve method and watershed comparative analysis method are used to comprehensively analyze the temporal and spatial law of sediment transport in typical granite watershed in South China. The results show that the granite basin has a higher sediment transport modulus than other basins due to the influence of the structure and mineral composition of the weathered granite soil. Taking the Wushui basin as an example, its value can be several times higher than that of the non-granite basin under the same meteorological conditions. Similar to many basins in China, the sediment transport modulus of Wushui basin also shows the characteristics of gradual decline, which is closely related to the "The Great Leap Forward", "Learn from Dazhai in Agriculture", "The Household Contract Responsibility System", "Return the Grain Plots to Forestry" and other policies, but different from many other basins, the three stages of sediment transport modulus change in Wushui basin are mainly caused by human activities The influence of the change of the cover is not significant.