The spatial distribution characteristics of soil organic matter and nitrogen in the natural floodplain wetland were studied in this paper. The results showed that the vertical distributions of nutrients in floodplain wetland were very similar, and the horizontal distribution of them in surface soil were distinctly different. The highest concentration of nutrients was not in the frequently-flooded floodplain wetland where the concentrations of soil organic matter and total nitrogen were 2.36% and 2605.4 mg/kg, but in the floodplain with a certain flood frequency. The concentrations of soil organic matter in the one-year floodplain wetland and five-year floodplain wetland were 3.70% and 3.92%, respectively; and the concentrations of total nitrogen were 3666.4 mg/kg and 3125.6 mg/kg, respectively. The ratios of carbon and nitrogen were relatively low. All the factors such as cycling of dry and wet, underground underset, vegetation growth and pH values etc. influenced the distribution of soil organic matter and nitrogen in wetland.