As a food resource in both Eastern and Western countries, the eel is an important fish. Over the years, remarkable progress has been achieved in understanding the mysterious life cycle of eels that has fascinated scientists since the age of Aristotle. The spawning area of the Japanese eel was discovered and the migratory route of its larvae was elucidated. With the development of techniques for artificial induction of gonadal maturation, it became possible to obtain hatched larvae. Larval rearing to the leptocephalus stage, one of the most difficult tasks involved in eel culture, finally was achieved. By presenting these important breakthroughs, Eel Biology will be of