Polydextrose is a kind of soluble dietary fiber, forms of which can be polyglucose powder, polydextrose syrup. Compared with insoluble dietary fiber, polydextrose fiber has more health function and processing advantage. Except the distinct functions with increase stool volume, enhance defecation, reduce intestinal cancer risk of insoluble dietary fiber, polydextrose soluble fiber also has the function of significantly decrease serum bile when combined with the remove of bile acids, more easily to lead to a sense of fullness, significantly reduce postprandial blood glucose levels and so on. For its characters of low calorie, stabilization, and extremely high tolerance, this kind of water-soluble dietary fiber is widely used in all kinds of food.