Soil organic carbon （SOC） stability and carbon sequestration potential can be affected by vegetation cover. The Caohai in Guizhou is a typical plateau freshwater wetland ecosystem at the same latitude as other regions worldwide. The study focused on the soils from Caohai and selected five types of vegetation cover, including forest land, cultivated land, grassland, reeds, and tidal flats. Soil samples were collected vertically at depths of 0-20, 20-40, and 40-60 cm, and the activity and stability of SOC were tested to explore the impact of different vegetation covers on the composition and stability of SOC, finally providing basic data for soil carbon sequestration and ecological protection in the Caohai. The results indicated that cover variability led to differences in SOC content on the vertical distribution scale （