Ecological restoration of water environment is in the increasingly widespread concern. Aquatic ecological restoration engineering technology guided by algaeeating daphnia controlling algae was applied to improve water clarity by input algae-eating daphnia, then taking such planting submerged aquatic vegetation as the focus of a series of ecological restoration measures to rehabilitate eutrophication landscape water. In reclaimed water supply conditions, the landscape waterbodies of the Yuanmingyuan implementation projects of aquatic ecological restoration were guided by algaeeating daphnia controlling algae. In Fanghe, Jianbiting, and Yulinglongguan during April to June 2008, and Fenglingzhou during September to November, 2007, water quality monitoring was carried out during and after the restoration. The result indicates that the main indexes such as turbidity, COD, TN, TP and Chla were improved greatly. After restoration, they were 1-2NTU, 6-11 mg/L, 0.28-0.98 mg/L, 0.019-0.044 mg/L, 2.1-8.5 mg/m3 respectively. Compared with before the restoration, the four indicators mentioned above decreased 74%-99%, 63%-87%, 77%-85%, 77%-85% respectively, and the water quality was II-III grade compared with V grade before restoration.