The construction of the Three Gorges Dam reservoir spans the Yangtze River, China, forming a hydro-fluctuation belt with a water level drop of nearly 30 m and an area of 300 km². The unique anthropogenic hydrological regime of the Three Gorges Dam has had significant negative impacts on the reservoir's riparian ecosystem. Some flooding-intolerant plants living within the belt gradually died off, which exacerbated vegetation habitat fragmentation and deleteriously affected the biological diversity, ecosystem structures, and functions of the water-fluctuation zone. Therefore, a pressing scientific challenge is to recover and restore the vegetation there and ensure proper ecological function. Previous studies have shown that Taxodium distichum is a flooding-tolerant plant and has been used for vegetation reconstruction. The nutritional characteristics of plants in a particular area can reflect the eco-physiological processes of plants, and can serve as crucial indicators of the structure and function of the local ecosystem. The nutritional characteristics play a key role in adaptation to anti-seasonal flooding, and might reveal clues about the adaptation mechanisms of plants in the hydro-fluctuation belt of the Three Gorges reservoir area. To contribute to this understanding, the nutritional characteristics of T. distichum growing in the reservoir riparian region of Zhongxian county, which had been planted in 2012, were studied. Element contents of three sample zones in low water elevation (165 m)-SD, high water elevation (170 m)-SL, and the control-CK(175 m) were determined in 2015. The macroelement, secondary element, and micronutrient contents in root and leaves of plants were measured. The results showed that:(1) Concentrations of N, P, K, Ca, and Zn in leaves and roots of T. distichum under flooding significantly decreased compared to CK, whereas Fe and Mn contents significantly increased. (2) Some nutrient concentrations of T. distichum under flooding decreased, but still maintained their normal performance. (3) Correlation analysis showed that plant heights were positively correlated with the concentrations of N, P, K, and Mg; plant heights were negatively correlated with the concentrations of Fe, Cu, and Mn; canopies of plants were positively correlated with the concentrations of N, P, K, and Mg, but negatively correlated with Fe and Mn. This investigation indicates that water level change had significantly influenced the nutritional characteristics of T. distichum in water-level-fluctuating zone of the Three Gorges Reservoir. T. distichum had good adaptability to the changed water habitat.