Abstract: The antioxidant components of Hong Guo Shen were ultrasonically extracted and purified using D-101 macroporous resin.The content of the extracts was determined using proanthocyanidins as index.The antioxidant activity of the purified extracts was investigated by testing scavenging effects of ·OH,O₂^-·,NO₂ and against the peroxidation of oils.The results showed that the purified extracts exhibited excellent ability to remove ·OH，O₂^-·,NO₂ and good inhibitory effect to peroxidation of oils.Furthermore,the antioxidant activity increased with the increasing of the concentration of extracts.

Key words: Hong Guo Shen, proanthocyanidins, extractions, antioxidant activity