Oat is a promising grain well-incorporated into human diet due to the presence of multiple nutrients in composition and its unique health-enhancing attributes. Similar to other cereals, starch is the most important component of the oat kernel, which makes up at least 60 % of the grain's dry weight. Considering the need to access new sources of starch with a broad range of capabilities, oat starch has experienced various modifications by physical and chemical strategies. Thus, this study aims to comprehensively review the impacts of various physical and chemical modifications on the physicochemical, functional, as well as digestibility properties of oat starch. Besides, the effects of oat starch combination with other biomacromolecules (whey protein isolate, caseinate, gums and lipids) on mentioned criteria were also reviewed. In conclusion, various modification methods could properly enhance the physicochemical attributes and digestibility of oat starch for its further successful application in food and pharmaceutical formulations.