Increased N concentration in an aquatic ecosystem is one of important causes of eutrophication. Aquatic higher plants in eutrophic water bodies can remove N by direct uptake and by being a carbon source and a surface substrate for microorganisms and algae, which also use N as a nutrient and can transform N into gaseous forms that escape from the ecosystem. Rooted submerged higher plants can transport oxygen to inundated soils, which increases microbial nitrification, thus providing NO3 – to the water column. Factors influencing N removal efficiency by aquatic plants include N and hydraulic loading, light, temperature, pH, season, plant harvesting, and availability of other nutrients. These factors differ for different plant species, therefore, plant selection for a particular wastewater treatment should be considered in an integrated approach