Abstract: Pectin was extracted and purified by acid-extraction and ethanol precipitation ultrasonic assistance from Hong Guo Ginseng. With the same concentration of ascorbic acid( VC) as the control, the antioxidant activities of pectin extracts was investigated by testing scavenging effects of ·OH,O2-·,reduction to Fe3+and against the peroxidation of oil and fats. The results showed that at the same pectin concentration of 0.6g/L,the scavenging rate to ·OH,O2-· was 40.53% and 26.02%,adsorption value was 0.51 by reducting Fe3 +,and the protect rate to oil and fat was 96.83% 39.22%,respectively. Furthermore,the antioxidant activity was increased with pectin concentration increasing.