Abstract: Abstract:Water eutrophication is one of the most challenging environmental problems in the world. The Taihu Lake Region in China is a typical eutrophication area. The discharge of domestic wastewater is one of the main sources of eutrophication. The effluent from wastewater treatment plants was as highly concentrated as 10 mg/L and was a pollution source to the natural water body. To effectively treat the effluent with low concentrations of N and P with low costs and in combination with a resources recycling function, different paddy wetland systems were designed to purify the effluent including traditional flooding overflow type and furrow irrigation infiltration type with two different ditch lengths in the paddy fields. In the two ditches, one was 116.0 m long and string-shaped, with the other one was 82.5 m long and arch shaped. The results showed that:1) At jointing and grain-filling stage of rice, N and P removal efficiencies in paddy wetlands were up to 77%-93% and 87%-96%, respectively, and TN concentrations in the discharge were uniformly lower than 2 mg/L. 2) The removal efficiency was highest for TN in overflow type wetlands and lowest in string-shape furrow irrigation infiltration type wetlands, while for TP, the arch-shaped furrow irrigation infiltration type paddy wetlands was the highest, but the differences were not significant among the three treatments. 3) The grain yield was the highest (8520 kg/hm²) in arch-shaped furrow irrigation infiltration type paddy wetlands due to the suitable area ratio of ditches to fields (8%), and increased about 5.2% compared with the overflow-type paddy wetlands, and lowest in string-shaped furrow irrigation infiltration type paddy wetlands for its high area ratio of ditches to fields (about 14%). This indicated that using widespread paddy fields in Taihu Lake Region to purify the surrounding effluent was effective.