When the water temperature was 16-22°C，the hydraulic load was 5 m³;/(m²·h) and the air-water ratio was 1 .5:1，the pollutants removal effects of the polluted lake water through the down-flow biological filter with the ceramisite，the activated carbon of 2 different particle sizes and the quartz of 2 different particle sizes were compared. The results show that the removal of COD_Mn，NH₄⁺ -N and TN by activated carbon filters were higher than quartz sand filters and ceramsite filter and the purification efficiency of small particle filter was higher than that of the large particle filter. The average removal rates of turbidity COD_Mn，NH₄⁺ -N and TN by small particle activated carbon filter were 84. 45 %，36. 82%，84. 55 % and 10. 19 %，respectively. The turbidity removal by quartz sandfilters was better than activated carbon filter and ceramsite filter and the removal efficiency of small particle was better than that of the large particle filter. The average removal rates of turbidity COD_Mn，NH₄⁺ -N and TN by small particle quartz sand filter were 87. 91%，32. 43 %，78 . 25 % and8.46%，respectively. For the large particle diameter ceramsite filter had lower turbidity removaland the average removal rates on turbidity, COD_Mn，NH₄⁺ -N and TN were75.63 %，35.79%，80.06% and 8. 85%，respectively.