The antioxidant activities of the root of Panax ginseng and the root bark of Acanthopanax senticosus were compared by in vitro and in vivo experiments. The results of in vitro experiments showed no significant difference between the antioxidant activities of both crude drugs. However, the results of in vivo experiments showed much higher antioxidant activities in Panax ginseng than Acanthopanax senticosus, showing about 80 times greater activity.