Recently, epidemiological studies confirm that dietary fiber intake is linked with a reduced risk of death. So, this review illustrated dietary fiber (DF) composition and classification. It also shows the extraction methods, factors that influence its functionality, and how it affects microbiota. The main components in oilseeds are fatty acids (FA), protein, dietary fiber, and other micronutrients. . Oilseeds DF are of great importance to human health by reducing the risks of some diseases. It also acts as an antioxidant, anti-bacterial, anti-cancer, anti-cholesterol, anti-cardiovascular, and anti-inflammatory agent, in addition to its role in diabetes, diarrhea, constipation, and obesity, as well as their utilization in the field of cosmetics.In this review, the health benefits of some popular oilseeds dietary fiber such as (flaxseed, cotton, sunflower, soybean, sesame, and mustard) were evaluated