The purpose of this study was to investigate the long-term carnosine administration and exercise antioxidant effect against free radical, the effect of carnosine administration and exercise on antioxidant defense system in rats. 28 rats were randomly divided into control group (n=7), exericse group (n=7), carnosine administration group (n=7), carnosine administration and exercise group (n=7) thus performed carnosine administration and aerobic exercise for 8weeks. The results of this study can be summarized as follow: MDA concentration were significantly lower in carnosine administration and exercise group, SOD activity and GPX activity was significantly higher in camosine administration and exercise group after 8weeks treatment. Endurance performance time was in carnosine administration and exercise group significantly longer than that of control group, exercise group, carnosine administration group on 7weeks. In conclusion, it was certain that camosine administration and aerobic exercise for 8weeks showed postive effect as antioxidant, which was prevent to body from induced radicals by antioxidant enzyme activity was increased in blood. Especially, long-term Carnosine administration demonstration to have positive effect on lipid peroxidation product decrease and on cell membrance damage decrease. But, Future study is required to mutiples research of change of carnosine concentration, concentration of hydrophobic antioxidant such as vitaminE, C and administration volumes.