1. Objectives The purpose of this study is to prove the anti-aging effects of Sipyimigwanjung-tang. 2. Methods The SD rats used in this experiment were 6, 18 and 36 weeks old. A part of the 36weeks was grown to 52 and 68 weeks at labarotary. Each age group was again divided into three groups. These 15 groups consisted of 6 rats each. One group was given no treatment, another group was dosed 200 ${mu}l$ of normal saline daily, and the last group was dosed 200 ${mu}l$ of 1% Sipyimigwanjung-tang(SYG) and saline mixture. At the conclusion of the experiment, the age groups were relabelled accordingly(10w, 22w, 40w, 52w and 68w). After 4 weeks, the tissue of liver, heart, spleen, lung, kidney and brain was biopsied in order to measure the SOD, GSH, MDA. 3. Results and Conclusions In liver, the activity of the SOD of 52w-SYG was significantly increased than that of 10w, 22w and 40w-SYG, the level of the GSH of 40w-SYG was significantly increased than that of the normal group, the activity of the catalase of 68w-SYG was significantly increased than that of the normal and control group, the level of the MDA of 52w-SYG and 68w-SYG was significantly decreased than that of the normal and control groups. In heart, the level of the GSH of 22w-SYG was significantly increased than that of the normal and control group. In spleen, the level of the GSH of 52w-SYG was significantly increased than that of the normal and control group. In lung, the level of the GSH of 52w-SYG was significantly increased than that of the normal group and the level of 68w-SYG was significantly increased than that of the normal and control group. In kidney, the level of the GSH of 10w-SYG was significantly increased than that of the normal group. In brain, the level of the GSH of 68w-SYG was significantly increased than that of the normal and control group. The SYG inhibited the histology degeneration of brain tissue. These results suggest that oral administration of SYG (Sipyimigwanjung-tang) decoction has anti-aging effects in aged rats.