The reproductive toxicity of genistein has attracted a certain attention from researchers worldwidely in recent years. Excessive intake of genistein may result in abnormal structure and function of reproductive system in animals (including male and female). However, the mechanism on which genistein impact on female reproductive system remains inexplicit. Oocyte, the physiological foundation to the normal reproductive function, has been considered as a potent target for exogenous chemicals. It is shown that genistein can interfere with the maturation process of mammalian oocytes, which may be one of the mechanisms of genistein’s reproductive toxicity.