Abstract:In order to improve the hydraulic permeability of wastewater infiltration system, two installations were designed with two with layers of red soil and cinder. At the load of 10 cm3/(cm2·d), the average removal efficiency of COD, TP, NH+4-N were different fillers for treating domestic wastewater at laboratory.1 installation was filled with layers of red soil and sand, while 2 obtained 91.1%, 97.6%, 48.7% and 80.1%,respectively by 1 installation; and 94.9%,98.3% and 89.0%,respectively by 2. The average effluent concentrations of nitric and nitrite were 54.7mg/L and 0.09mg/L by 1 installation; and 60.3mg/L and 0.15mg/L by 2. It was found that the removal efficiency of COD,TP and NH4+-N by 2 installation were better than those of 1, whilst 1 installation was more favourable for the removal of nitric and nitrite. The results further implied that layeredfilling can make good use of its filling performance. The hydraulic permeability of wastewater infiltration system and the removal of pollutants can also be effectively improved.