Abstract：Flocculating method is an economical and conveniet water treatment method to improve water quality at home and abroad and flocculants is the core of flocculating method．The research into flocculating theory provides safety for flocculants products．Comparing with traditional flocculants，the biofloeculant has the advantage of safety and without secondary pollution．This paper introduces research situation of bioflocculants and makes expectation f0r its development trends．