Dietary fiber has good physiological function and plays an important role in human health. This paper reviews the modification of dietary fiber in food by-products by steam explosion technology and its influence on structure, physical and chemical properties and functional properties of dietary fiber. Steam explosion treatment can change some insoluble dietary fiber into soluble dietary fiber. It’s expected to increase the content of soluble dietary fiber in food and its by-products and improve the quality of dietary fiber, so as to apply high-quality dietary fiber in food processing and improve the utilization rate of dietary fiber. Steam explosion treatment can significantly improve the physical and chemical functional characteristics of dietary fiber, helping to develop functional food of dietary fiber.