To optimize the efficiency of surface flow constructed wetlands purifying the polluted water, eight different wetland plants(including emergent, submerged and floating leaf plants)were selected to construct eight wetlands to monitor and compare their removal rates of nitrogen and phosphorus pollutants. The results showed that wetlands with emergent plants Hydrocotyle verticillata and Myriophyllum aquaticum are the most applicable to further treat tail water as they grew densely. The average removal rates of TN, NO^-₃-N and NH₃-N were 68. 6%, 62. 6% and 78. 2% respectively and the average removal rates of TP and DIP were 64. 5% and 80% respectively. Wetlands with floating leaf plants Nymphaea L. also showed a certain potential for nitrogen and phosphorus removal and the average removal rates of TN, NO^-₃-N, NH₃-N, TP and DIP were 55%, 55. 2%, 63. 3%, 56. 1% and 64. 7% respectively. Submerged plants Vallisneria natans(Lour. )Hara lost its dominant position gradually when competing with Hydrocotyle verticillata to purify the tail water. Even though emergent plants Iris pseudair L. and Thalia dealbata had large amount of biomass, the wetlands with these plants exhibited low pollutants removal ability. The pollutants removal rates of Thalia dealbata wetlands were especially low, with nitrogen removal rates only between 18% and 36. 2% and TP and DIP removal rates only about 41. 5% and 38. 7%, respectively. So it would be better to choose emergent plants such as Hydrocotyle verticillata and Myriophyllum aquaticum rather than other emergent plants when using surface flow constructed wetlands to remove nitrogenous and phosphorus pollutants in tail water from sewage treatment plant.