Top soils (0-10 cm) were collected along a water gradient in three sampling belts in Caohai wetland of Guizhou Province, including agricultural areas, transition areas, shallow-water areas and deep-water areas. Soil total organic carbon (TOC), total nitrogen (TN), total phosphorous (TP) and their ecological stoichiometry in different water levels were measured to investigate their horizontal distribution patterns, as well as their influencing factors. Our results showed that the difference of TOC, TN and TP contents were significant in four water gradients. The soil TOC and TN contents gradually increased from the transition areas to the deep-water areas, while the TP content firstly decreased and then increased. The soil TN content in agricultural areas were significantly higher than that in the shallow-water areas, but TP content in the deep-water areas were significantly lower than that in the agricultural areas. The difference of soil C/N, C/P and N/P ratios were significant in four water levels. The soil C/P and N/P ratios gradually increased from the transition areas to the deep-water areas, while the C/N ratios firstly increased and then decreased. Compared with the transition areas, the soil C/N, C/P, and N/P ratios in the agricultural areas were lower. Correlation analysis showed that the spatial distribution of soil C/N, C/P and N/P ratios were related to soil physical and chemical properties such as TOC, TN and water content. In summary, the hydrology significantly affects the spatial distribution of soil TOC, TN, TP, C/N, C/P and N/P ratios in Caohai wetland, and the accumulation of soil carbon and nitrogen will be enhanced when the water level rises.