The dietary fat intake of Japanese is thought to be more appropriate than in Western countries; however there is a range of differences of individuals in the amounts of fat intake and n-6/n-3 ratio. Therefore, it is important what kind of vegetable oils are used for cooking in order to consider the total balance of fat intake. Rice bran oil (RBO) is expected to reduce plasma cholesterol and be useful for prevention of cardiovascular disease because it contains several effective ingredients. RBO is rich in linoleic and oleic acid. RBO contains γ-oryzanol, which is well known to reduce plasma cholesterol levels. Furthermore, it contains tocotrienols, which are analogs of vitamin E, reported to have unique bioactivity different from that of α-tocopherol. The biological function of these components and their potential to prevent Japanese lifestyle-related diseases are discussed.