Poyang Lake of Jiangxi Province is the largest freshwater lake in China. There are abundant aquatic plants, including flowering plants of 37 families, 70 genera, 98 species. Although Poyang Lake is located in the subtropic zone, the floristic elements are complexly composed of the common species of subtropic-temperate, tropic-temperate and cosmopolitan. As compared respectively with the floras of Lugu Lake, Honghu Lake, Baiyandian Lake and Jingbo Lake, the flora of Poyang Lake is found more similar to that of Honghu Lake than to those of the other lakes, showing that the flora of Poyang Lake has a, character of subtropic.