Abstract: In order to investigate the influence of ultrasonic treatment in food processing for raw materials rich in anthocyanin, in this research, cyanidin from mulberry extracts were used as materials. The effects of ultrasonic waves on cyanidin stabilities and antioxidant activity were investigated. Further, the relation between the hydroxyl radical scavenging and anthocyanin degradation in ultrasonic treatment was analyzed. Experimental results showed that the ultrasonic treatment could lead to partial degradation of anthocyanins. With the intensity increasing, the stability of anthocyaninsin significantly reduced and antioxidant capacity was weakened. When the ultrasonic power was increased from 200 W to 500 W, processing time increased from 15 min to 90 min, the scavenging rate to ·OH of the sample decreased by 40% on average and antioxidant activity decreased by5%⁷0%.