A study was amino acid contents by heating conditions of mackerel, pacific saury , yellow croaker, and brown sole investigated. In fresh fishes, total amino acid contents showed higher amount in brown sole and yellow croaker, than those of pacific saury and mackerel. The amino acid contents among the tested samples were higher Glx , leucine, lysine and arginine in order. During heating of samples the amino acid contents decreased. There appeared to be a proportional relationship of the heating temperature to decrease of amino acid. The amino acid contents of steamed samples significantly decreased than those of others. During warming and rewarming samples after storage at 4$^{circ}C$ for 24 hours , amino acid contents slightly decreased.