Abstract: In this study, the changes of myofibrillar protein and its properties, including carbonyl content, dimeric tyrosine content, mercapto content and the content of myofibrillar protein were studied, which were caused by protein oxidation, as treated by free radical oxidative system.The hydrophobicity of myofibrillar protein was observed and the hydrolysis of the protein was observed by SDS-PAGE. The simulated oxidation was carried out by free radical oxidation system ( including FeCl₃ and ascorbic acid concentration of 0.1 mmol/L, hydrogen peroxide concentration of 0, 1, 5, 10 mmol/L) and were oxidized 1, 3 and 5 h.The results showed that the carbonyl content, dimeric tyrosine content and surface hydrophobicity of mycelial fibrils were significantly increased ( p < 0.05) with the increasing of oxidant concentration after oxidation of free radical oxidative system free thiol content decreased significantly ( p < 0.05) . It can be seen from the SDS-PAGE gel that the higher the concentration of oxidant, the more obvious hydrolysis of the treated protein.It can be concluded that free radical oxidation affected the carbonyl content, dimeric tyrosine content, mercapto content, hydrophobicity and the hydrolysis of protein of myofibrillar protein.