Abstract: Samples were collected once a month from March 27th to November 6th (8 times aggregately) from the water of west Wuli lake, released with suspension-feeding animal such as spiral shell (C. cathayensis), mussel (Hyriopsis cumingii), silver carp (Hypophthalmichthys molitrix) and bighead carp (Aristichys nobilis), a mode of eco-restoration method, and the water in east Wuli lake were sampled at the same time, as the control. Total phosphorus (TP), total nitrogen (TN), nitrate nitrogen (NO3--N), nitrite nitrogen (NO2--N), ammonium nitrogen (NH4+-N), CODMn and chlorophyll-a (Chla) in the samples were analyzed at laboratory and pH value, transparency (SD) and dissolved oxygen (DO) of water in the sampling locations were also monitored at the time of sampling, witch were used as main quality indexes for evaluation of effect of the eco-restoration method on purifying eutrophication water. Results showed that in the eight times of monitoring after releasing suspension-feeding animal in west Wuli lake, transparencies in west Wuli lake taken on a trend of increasing, and the mean value improved by 26.8%, with the biggest value of 60cm improved by 91.7%, compared with that of the background. Concentrations of total phosphorus in west Wuli lake decreased and the total phosphorus achieved the Ⅱclassification of environmental quality standard for surface water (GB3838-2002) at the time of March, April, May, June, July and November, accounting for 75% of the total monitoring times. Although total nitrogen belonged to the below Ⅴ classification of environmental quality standard for surface water (GB3838-2002), it decreased compared with that of the background. The comprehensive trophic state indexes (TLI(∑)) changed from the west Wuli lake being higher than the east Wuli lake before releasing suspension-feeding animal to the east Wuli lake being higher than the west Wuli lake after releasing suspension-feeding animal. So, releasing spiral shell, mussel, silver carp and bighead carp in eutrophic lake could improve transparency, reduce nitrogen, remove phosphorus effectively and make the degree of eutrophication decrease finally.