Abstract: Lactic acid bacteria( LAB) were important probiotic microorganisms and critical industry bacteria,which were widely used in fermentation foods. The fermentation productions which produced by LAB were attracted great attention. This paper provided an overview of the main physiological and biochemical functions of exopolysaccharide( EPS) which produced by LAB. Besides, four metabolic pathways which related to exopolysaccharide biosynthesis also had been summarized, in order to provide evidence for the EPS applications,raising yields and structure modification.