Abstract: The use of microbial agents for bioremediation of polluted water has the characteristics of cost-effectiveness, low energy consumption and no secondary pollution. In recent years, great progress has been made in the research and application of microbial agents in water remediation, which has become one of the research hotspots of water bioremediation technology. Through literature search and patent statistics, the research and application status of microbial agents at home and abroad were analyzed. The principle of microbial agents in water remediation and the removal of nitrogen, phosphorus, heavy metals and refractory organics in water were reviewed. The preparation process of microbial agents was briefly introduced, and the application of microbial agents in the repair of black and odorous water bodies, aquaculture water bodies and micro-polluted water sources was summarized. Finally, the problems of microbial agents in water remediation were analyzed, and their development prospects forecasted.