The effect of HWANSODAN(HSD), on the level of brain antioxidants was examined in aged rat. The experimental groups were divided into three groups and treated as follows ; normal group(negative control), Vt.E administrated Group(HSD). The purified microsome from brain tissue, those were measired the amounts of oxidant materials like Malonfialdehyde(MDA) and H2O2, then activities of antioxidants enzymes like superoxide dismutase, catalase, NADPH-cytochrome P-450 reductase.The results were as follows;1. In TBA reaction to measure the amount of MDA, HSD group and Vt.E group did not showed signigicant decrease.2. In the formation of Hydrogen peroxide, HSD group and Vt.E group showed a little increase.3. The activity of Superoxide dismutase was increased significantly in HSD group and Vt.E group.4. In the activity of Catalase, Vt.E group was increased significantly and HSD group a little increased. 5. The activity of NADPH-cytochrome P-450 reductase in the HSD group and Vt.E group showed significantly increase.According to the above results, it is suggested that HWANSODAN(HSD) has some antioxidant effects on the tissue of brain.