Abstract: Oat (Avena sativa L.) is an annual grass plant of the Gramineae family and Oat genus. Starch is the most abundant component in oat and account for about 50%~65% of the dry weight of grain. The common methods for extracting oat starch include alkali extraction, enzyme extraction and water extraction. The unique structural characteristics of oat starch and its low thermal stability, paste transparency, shear resistance and high viscosity properties directly affect the thermal stability and viscoelastic properties of oat products. The modification of oat starch by thermal (steaming, baking, superheated steam, microwave, extrusion, infrared, steam explosion, etc.) and non-thermal (pulsed electric field, low temperature plasma, high hydrostatic pressure, ultrasonic wave, etc.) treatment methods can improve its hydration properties as well as the organoleptic and eating qualities of the product, which will greatly enhance the market competitiveness of oat starch. It is also expected to use oat starch as a unique source of starch for various applications. At present, the understanding of the mechanism of physical modification of oat starch is still limited, and more research is needed to explore the mechanism of physical modification of oat starch from the aspects of molecular structure and physical and chemical properties. In this paper, recent advances in the extraction, structure, physicochemical properties and physical modification of oat starch were reviewed, in order to effectively promote the development and utilization of oat based food.