<;P>;PROBLEM TO BE SOLVED: To provide a method for preventing color deterioration of the flesh of yellowtail by which deterioration particularly in color of dark flesh during low-temperature storage of the yellowtail is effectively prevented. <;P>;SOLUTION: The method for preventing deterioration in color of the flesh of yellowtail comprises using feed containing 5-100 mg/kg of astaxanthin, and &gamma;-oryzanol at an amount of at least 7 times that of the astaxanthin; and posing a period of two months or more for breeding the yellowtail so as to effectively prevent deterioration in color of dark flesh of the yellowtail during low-temperature storage thereof. <;P>;COPYRIGHT: (C)2011,JPO&INPIT