Abstract: To investigate the impact of ultrasound-assisted curing on the quality attributes and protein oxidation of stir-fried chicken dices and its underlying mechanism, chicken dices were cured under ultrasound conditions (120 W, 40 kHz) for varying durations (0, 30, 60, 90, 120, 150 min). Changes in physicochemical properties, texture characteristics, sensory quality, oxidation indicators, and protein digestibility were systematically analyzed. The results demonstrated that ultrasound-assisted curing significantly increased the moisture content of stir-fried chicken dices (P<0.05) and improved color parameters, with the 90-min treatment group exhibiting optimal L^* and a^* values (60.83 and 7.44, respectively). Texture profile analysis revealed that ultrasound treatment significantly reduced hardness (from 3474.99 g to 2673.61 g) and chewiness, effectively enhancing tenderness. Protein oxidation analysis indicated that ultrasound accelerated the oxidation process of myofibrillar protein, characterized by a decrease in total sulfhydryl group content and an increase in carbonyl group content. However, SDS-PAGE results confirmed no significant protein degradation occurred. With the extension of ultrasound time, the in vitro digestibility of protein significantly increased from 46.3% in the control group to 86.4% in the 150-minute group, while the digestibility of the 90-minute treatment group was 72.3%, and the overall sensory score significantly improved. When the ultrasound treatment duration exceeded 90 min, excessive protein oxidation occurred, leading to quality deterioration. Comprehensive analysis identified 90 min as the optimal ultrasound-assisted curing time. Under these conditions, stir-fried chicken dices exhibited the best texture characteristics, sensory quality, and nutritional value.