Objective To observe the effect of Natural mountain spring on oxidative damage of aging mice. Methods Thirty male aging mice were randomly divided into experimental group(drink Natural mountain spring) and control group(drink tap water) according to the level of MDA. The serum in the two groups was taken for T-SOD activity and MDA content analysis after two months. Results The MDA content in experimental group decreased markedly than that in control group. Conclusion Natural mountain spring could alleviate oxidative damage by free radicals to extent.