Abstract: Ultrasonic treatment has become an important green and low-cost nonthermal processing technology for starch modification. Starch is treated in an ultrasonic water bath or ultrasonic probe to regulate and improve its multi-scale structure. In this study, the mechanism of ultrasonic starch modification is introduced, and the changes in the particle, molecular, and crystalline structures with treatment as well as the methods for characterizing these changes are reviewed. The effects of ultrasonic modification on the physicochemical properties of starch (swelling force, solubility, gelatinization, and rheological properties) are then discussed. Furthermore, the influence of ultrasonic treatment on the multi-scale structure of starch and its digestion behavior is analyzed. This study provides a theoretical basis for the application of ultrasonically modified starches in food.