Abstract: As a new type of extracellular polysaccharide,Welan gum could be secreted by Sphingomonas sp.,and is composed of four sugar units:D-glucose,D-glucuronic acid,L-rhamnose and L-mannose. Welan gum has functions of thickening,emulsifying,suspending and stabilizing in production and application. Due to its characteristics of high application value and pollution-free,welan gum has been widely used in various industrial fields,such as food,medicine and oil,showing great potential for further industrial application. In this review,the structure and property of Welan gum,the arobolic pathway of Welan gum,the optimization of production process of Welan gum,the improvement of its economical efficiency separation and purification are reviewed.