A lot of experiences were conducted in different hydraulic retention time(HRT),temperature and COD/N to explore the removal efficiency of TN,NH₃-N in the water using the wavy subsurface constructed wetland(W-SFCW) test device,and to discuss the nitrogen removal principle by detecting nitrogen removal content in various forms along the path of W-SFCW device.The results showed that total nitrogen rate was higher and could amount to 74.92% when HRT,temperature,COD/ N were 5 d,26.8℃,5,respectively.In addition,we found that ammonia nitrogen was mainly in shallow water through the nitrification into NO₃-N,and the NO₃-N was removed through the deep water denitrification into Nz in the deep water.