Abstract: Alternansucrase(EC 2.4.1.140)is a kind of glucansucrases with transglycosidase activity,and it catalyzes the polymer synthesis from sucrose or acceptor reactions in the presence of acceptors. Its acceptor reaction can be used to produce oligosaccharides with prebiotic activities,modify starch,enhance the solubility of flavonoids or reduce the bitterness of steviosides,which makes this enzyme have potential applications in food,feed,cosmetics and pharmaceutical industries. In this review,the research status of microbial alternansucrases was summarized,including strain breeding,biochemical properties,three-dimensional structure,acceptor reaction and potential applications. Besides,future perspectives of alternansucrase were also highlighted,with a hope to guide the further study of microbial alternanscurases and the development and utilization of related products.