In this study, myofibrillar protein was used as the research object to investigate the effect of different frozen storage time on the oxidation degree of myofibrillar protein of pork. Raw pork was stored at 18 ℃ for different time (0, 1, 4, 8, 12 weeks), and used for the extraction of myofibrillar protein. Then protein oxidation parameters (carbonyl, total sulfhydryl group, free amino groups, surface hydrophobicity and endogenous tryptophan fluorescence) were determined. The results suggested that, carbonyl content increased significantly (P＜0.05), and total sulfhydryl group, free amino groups, surface hydrophobicity and endogenous tryptophan fluorescence content generally showed a decreasing trend (P＜0.05). There is a correlation between storage time and carbonyls, total sulfhydryl group, free amino groups or surface hydrophobicity. Therefore, myofibrillar protein will be oxidized during the frozen storage, resulting in the degradation of raw meat quality.