The present invention relates to a method of antioxidative functional estimation using an animal model, more precisely a method of antioxidative functional estimation using mice having oxidative damage caused by reactive oxygen species induced by irradiation and having lipid hydroperoxide secreted in the urine which might be index for quantitative and qualitative analysis for antioxidative functional estimation. The method of antioxidative functional estimation of the present invention can be effectively used for the screening of a novel anti-oxidant agent or antioxidative functional health food to regulate the production of lipid hydroperoxide.