To investigate antioxidative and antiaging effects of yellow and black soybeans in vivo system, male SD rats (n＝24) were fed the diets containing casein (C), yellow soybean (YS) or black soybean (BS) for 8 weeks. Experimental groups showed the preventive effect on lipid and protein oxidation, especially protein oxidation of plasma was significantly inhibited in BS group. SOD and catalase activities were not different among the groups, but hepatic glutathione peroxidase (GSH-px) activity was significantly lowered in YS and BS groups compared with control group. The contents of superoxide anion radical in cytosol were significantly lowered in experimental groups compared with control group. And hydroxyl radical was slightly lowered in soybean groups. Lipofuscin accumulation on the heart and eyes of rats was effectively inhibited by yellow soybean and black soybean, respectively. In conclusion, these results suggest that yellow soybean and black soybean have the antioxidative/antiaging effect in vivo system and they have similar activities despite different color of seed coat.