The water quality of Chendun reservoir area from September 2015 to August 2016 was monitored. The variation of nitrogen and phosphorus concentration in wetland was summarized by analysis of variance. The interaction between nitrogen and phosphorus in different plants was discussed by correlation analysis. The results showed that the seasonal variation of TN and TP concentrations in the Chendun reservoir area was different. The TN concentrations in the functional areas were different in spring, summer and winter. There were significant differences of TP in the sampling points in the winter and no significant differences in other seasons. The variations of TN and TP concentrations were closely related to the influent nitrogen and phosphorus concentrations, wetland area, water depth, plant type and growth status. Different plants showed different correlation with wetlands TN, TP, which is related to the absorption capacity of aquatic plants on nitrogen and phosphorus. Among them, the leaves of Hydrilla verticillata, Thalia dealbata Fraser and Phragmites australias Trin,Reed have better removal effect on nitrogen and phosphorus.