Objective To investigate the mechanism of carnosine on anti-oxidating and anti-aging .Methods In this test, the oxidative carbonyl protein in brain tissue was prepared by H 2O 2. The brain tissues were homogenized and then were divided into three groups:control group, damage group by H2O2 and protection group in which carnosine was added before. Content of oxidative carbonyl protein and the level of oxidative phosphorylation were determined by the means of DNPH and phosphate consumption respectively. Results The content of oxidative carbonyl protein was lower in protection group than that in damage group (P0.05), and the level of oxidative phosphorylation was also higher in protection group than that in damage group (P0.01).Conclusions The study indicated that carnosine inhibited the generation of oxidative carbonyl protein and protected brain tissue from damage caused by H 2O 2.