Abstract:In order to solve the problem of eutrophication of water bodies caused by the discharge of a large amount of substandard domestic sewage into the river. A vertical flow artificial wetland was constructed using nano-mixed packing as the substrate,the Myriophyllum verticillatum L. as the wetland plant, and the domestic sewage was treated as the object. The removal effects of ammonia nitrogen (NH+4-N), total nitrogen (TN), total phosphorus (TP) and chemical oxygen demand nitrogen (COD) in domestic sewage in constructed wetlands and the purification effects of domestic sewage were analyzed. The results showed that (1) nanofillers had a greater effect on the purification effect of wastewater, and their average removal rates of COD, TN and NH+4-N could reach 88.7%, 93.4% and 97.0%, respectively, which were 7.91%, 10.99% and 11.02% higher than those of the system with pure sand without nanofillers added, respectively. (2) The planting of foxtail algae could improve the removal effect of the system on pollutants. The removal rates of COD, TN and NH+4-N in CW-2 were 6.52%, 11.86% and 7.31% higher than those in CW-1, respectively, and the removal rate of COD, TN and NH+4-N of CW-4 were 0.48%, 6.93% and 3.71% higher than those of CW-3, respectively.