Sampling and monitoring analysis was conducted over a period of 18 months in the Jinhe River Basin, and the dominant species causing the algae bloom in the river were identified through microscopic examination. The results show that the Jinhe River has been in a eutrophic state on the whole over the last two years, especially in July and August, when severe eutrophication has taken place, and microcystic cyanobacteria have largely contributed to the algae contamination. The applicability of inorganic coagulants to algae contamination control was investigated, using chlorophyll a, turbidity, and UV₂₅₄ as the major water quality parameters. The effects of four kinds of coagulants in controlling the algae contamination were compared. The results show that the inorganic coagulants were effective in controlling algae contamination of the Jinhe River(the removal rates of chlorophyll a and turbidity reached 89% and 92%, respectively, when polyaluminium chloride was used). Under the same experimental conditions, the four coagulants were ranked by performance in the following descending order: polyaluminium chloride, polymeric ferric sulfate, ferric chloride, and aluminum sulfate.