Flocculation sedimentation is an important process in water treatment. Microbial flocculants with safety and non-toxic properties have been used in water supply treatment and wastewater treatment, so the research and development of microbial flocculants are one of the hot spots of scholars. In this paper, the species and metabolic pathway of floc producing microorganisms, the research status of the flocculating mechanism of microbial flocculants and the application of microbial flocculants in water pollution control was reviewed. On this basis, the existing problems in the research of microbial flocculants were analyzed, and the main development trends of microbial flocculant research in the future were proposed, which could provide reference for related researchers.