Adenomyosis of the uterus is a relatively common gynecologic disease characterized by the presence of ectopic endometrial glands and stroma within the myometrium. Small cystic spaces (not larger than several mil-limeters) are invariably present, and these are filled with blood. Extensive hemorrhagic cystic adenomyosis,however, is rare, and there have been very few radiologic reports of this condition. We describe the CT and MRI features of three cases of histologically confirmed huge cystic adenomyosis.