Abstract: Composited algaecide was prepared by permanganate,aluminum chloride,sodium chloride and acid- soluble cuprous chloride. The effectiveness of composited algaecide on algae removal and the impact of nitrogen and phosphorus were studied. Algae cell morphology was observed by optical micrographs. The results showed that the composited algaecide effect on algae removal was obvious,the best removal rate of turbidity and chlorophyll a were 99. 81% and 97. 87% respectively,and nutrient was controlled effectively. The minimum residue of TN and TP were 1. 01 mg·L ^-1 and 0. 021 mg·L ^-1 respectively. Optical micrographs showed that the cell wall did not rupture,cytoplasm aggregated and cell shrunk,algal cells bonded together to form dense layer of sediment. The composited algaecide has a good effect on algae removal.