I have studied on the Enzymes of rice bran during preservation heating at various periods at constant temperatures and under atmospheric pressure. I found following facts through experiments. 1. It increases A. V. ratio of rice bran oil at above 120$^{circ}C$., but it does not effect on its fat by heating. 2. It increases A. V. ratio of rice bran oil rapidly at below 90$^{circ}C$., while it does not effect on its fat during preservation.