Abstract: The antioxidant is safe for human health, has excellent antioxidation activity and is suitably utilized for preventing oxidation of unsaturated fatty acids, esters of unsaturated fatty acids and various kinds of products comprising these acids and esters. The oxidation resistant polyunsaturated oil is made by giving strong antioxidation activity to polyunsaturated oils, such as polyunsaturated fatty acids, esters of polyunsaturated fatty acids and polyunsaturated fats.The antioxidant comprises musizin and tocopherol as the effective components. The oxidation resistant polyunsaturated oil and fat of the invention is characterized in that an antioxidant comprising musizin as the effective component is added to a polyunsaturated oil.