We are working on improving polyunsaturated fatty acid (PUFA) productivity of microorganisms and on developing technologies to efficiently acquire PUFAs. PUFAs such as docosahexaenoic acid (DHA, 22:6) and eicosapentaenoic acid (EPA, 20:5) are among the essential nutrients, which can hardly be synthesized in vivo. These PUFAs are known to reduce the risk of coronary heart disease and to alleviate inflammatory diseases. Then, PUFAs are expected to be used as health foods and pharmaceutical raw materials. We also aim to advance the biotechnological methods of PUFA-containing lipid production using biosynthesis genes for PUFA obtained from microorganisms and algae.