Treatment of polluted river water with variations of water quality using pilot-scale Surface Flow Constructed Wetland (SFCW) in Xinyi River Floodplain,Jiangsu Province was studied in this paper. The main results show that： When the influent concentrations of COD_Mn and NH⁺ ₄ -N were 11. 69 -60. 00 mg/L and 1.37-20, 18 mg/L, the COD_Mn and NH⁺ ₄ -N removal rate of SFW which planted Lythrum salicaria, Canna indica, Typha latifolia and Scirpus locustris were 26. 44% ,40. 12% ,46. 71% ,28. 23% and 64. 27% ,70. 49% ,66. 78% ,58. 52% , respecfioely. Typha latifolia and Canna indica have stronger ability for purifying pollutants. Scirpus locustris has the strongest ability of inundation, it can resist inundation of over 22 days and still live. Lythrum salicaria has the lowest ability of inundation, it only can resist inundation of 7 days.