Abstract:Soybean isoflavones，also known as plant estrogen，is a secondary metabolite produced by soybean and other family Papilionaceae plants.Previous studies have demonstrated that isoflavones play an important role in anticancer，antioxidant，prevention of osteoporosis and cardiovascular disease effects.Microbial fermentation technology can be used to produce different secondary metabolites with greater bioactivity than unfermented samples，which could improve the health benefits of food matrix.This article reviewed on the metabolism and bioconversion effects of the major monomers of soybean isoflavones by different microbial systems and their subsequent effects on the biological activity，and provided a theoretical basis for in-depth research on the microbial biotransformation of soybean isoflavones as well as the development of new functional foods.