Abstract: Dietary fiber is known as "the seventh nutrient". Reasonable intake of dietary fiber can regulate human physiological function,improve health and prevent disease. China has abundant seaweed resources,and is the world's top producer of edible seaweeds for a long time. Recent studies from around the world have indicated that edible seaweeds are rich in dietary fiber components that cannot be digested and absorbed by the human body,the components are mainly comprised of polysaccharides which have unique physical and chemical properties and significant physiological effects. Therefore,there is considerable development potential to extract dietary fiber from edible seaweeds and utilize it in healthy food processing and manufacturing. In this paper,the separation,purification,and physicochemical characterization of typical soluble and insoluble dietary fiber components in edible red algae,brown algae and green algae are summarized,so as to provide references for the research and development work in the field of health food and deep processing of economic seaweeds in China.