Abstract: The ultrasonic assisted extraction technology of anthocyanins from blackberry was studied, and the response surface design was applied to analyze the influence of extration temperature, the raito of solid to liquid, extraction time and ultrasonic power on the extraction. The effect of blackberry anthocyanins on 1,1-diphenyl-2-picryl-hyrazyl (DPPH),?O2- and?OH scavenging were also studied. The results indicate that the optimum extracting conditions of blackberry anthocyanins are as follows: the temperature 70.9℃, the extraction time 30.5 min, the ratio of solid to liquid 1︰9.14, and the ultrasonic power 526.9W. Besides, scavenging activity of blackberry anthocyanins on DPPH,?O2- and?OH are higer than tea polyphenol. When the concentration of blackberry anthocyanins is 3.0 μg/mL, the clearance rate of DPPH,?O2- and?OH are 82.54%, 79.90% and 65.90% respectively, and the scavenging activity is correlated with the concentration of blackberry anthocyanins.