Based on the typical wetland included Nanji Wetland, Wucheng National Nature Reserve, Baishazhou National Wetland Park and Longkou Wetland of Poyang Lake, we investigated the submerged macrophyte communities and sampled the water and sediment specimens in September of 2013. We also determined the contents of copper, lead and cadmium in water and sediment specimens and evaluated the heavy metals pollution in sediments by using both the Geo-accumulation index methods and the potential ecological risk index methods. According to the census data of submerged plant communities, we calculated the submerged macrophyte community structure by using both Shannon-Wiener diversity index and Pielou evenness index, and analyzed the correlation of the biomass and diversity of submerged plants and the heavy metals pollution in the water and sediment with Pearson correlation analysis. We also aimed to reveal the status of heavy metal pollution in the wetland of Poyang Lake and explore the influence of copper, lead and cadmium on submerged macrophytes in order to prevent and control the pollution of heavy metals and protect and restore the submerged macrophytes preferably. The results indicated that the highest content of heavy metals in water and sediment samples is Lead. All heavy metals in the water specimens were lower than the surface water environmental quality standard of class Ⅲ criterion except the content of lead in the sampling sites of Baishazhou. The highest content of heavy metals in the water of the sampling sites was in Baishazhou National Wetland Park located in the east of Poyang Lake, and the contents values ofρ(Cu),ρ(Pb) andρ(Cd) were 50.826μg·L-1, 68.660 μg·L-1 and 0.337μg·L-1 separately, while the lowest content of heavy metals in Nanji Wetland which located in the southwest of Poyang Lake, and the contents values ofρ(Cu),ρ(Pb) andρ(Cd) were 4.316μg·L-1, 7.301μg·L-1 and 0.167 μg·L-1 separately. The results indicated that Longkou was the severest heavy metal-polluted areas in sediments, probably because the water from the downstream of Lean River. But some differences exist in both evaluation methods: the Geo-accumulation index showed moderate pollution or light pollution in the sediments for all sampling sites, while the potential ecological risk index showed slight pollution in the sediments in all sampling sites. On the other hand, there were 11 submerged macrophyte species in 7 families and 9 genera in the investigated areas. The species diversity of submerged macrophytes in Nanji wetland was rich but the evenness of species distribution was relatively low. The results of Pearson correlation analysis suggested that there was no significant correlation among the biomass, species diversity and the heavy metal contents in the water and sediments.%对鄱阳湖南矶山湿地、吴城自然保护区、白沙洲国家湿地公园及鄱阳湖龙口等典型湿地进行沉水植物群落的调查与采样，并测定各样点水样及底泥重金属含量，采用地累积指数法和潜在生态危害指数法对底泥重金属污染进行评价，采用Shannon-Wiener多样性指数和Pielou均匀度指数等方法对研究区沉水植物群落结构进行评价，对水体、底泥重金属含量与沉水植物的生物量、物种多样性等进行Pearson相关性分析，评价鄱阳湖湿地水土环境重金属污染现状，探讨水体与底泥重金属Cu、Pb、Cd等污染物对其水体沉水植物群落的影响。结果表明：各采样点水体与底泥中Cu、Pb、Cd等3种重金属元素中含量最高的为Pb；各样点水体（除白沙洲水体ρ(Pb)外）ρ(Cu)、ρ(Pb)和ρ(Cd)等均未超出地表水环境质量Ⅲ类标准限值，水体重金属含量最高的区域为鄱阳湖东部的白沙洲（ρ(Cu)为50.826μg·L-1，ρ(Pb)为68.660μg·L-1，ρ(Cd)为0.337μg·L-1），最低的区域为鄱阳湖西南部的南矶山湿地（ρ(Cu)为4.316μg·L-1，ρ(Pb)为7.301μg·L-1，ρ(Cd)为0.167μg·L-1）。两种重金属污染评价方法的结果均表明，受纳乐安河下游来水的龙口区域为底泥重金属污染最严重区域；但两种评价方法的结果存在一定差异，地累积指数法评价龙口区域的结果为偏中度或轻度污染，潜在生态危害指数法的评价结果为轻度污染。研究区野外调查中共发现11种沉水植物，隶属7科9属，其中南矶山湿地的沉水植物物种多样性较丰富，但其物种分布的均匀度较低，水体与底泥重金属含量与其水体中沉水植物的生物量或物种多样性间无显著相关性。
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