The ectopic ovary is a rarely reported gynecologic entity. A variety of synonymous terms have been used to describe this condition, such as supernumerary ovary, accessory ovary, and ovarian implant syndrome. The etiology of ectopic ovary is poorly understood. The ectopic ovaries may occur in two ways. First, in the embryonic theories, they are believed to result from abnormal separation of a small portion of the developing and migrating ovarian primordium. Second, the accessory ovary can occur from acquired conditions such as inflammation and operations. In this report, we describe a case of the ectopic ovary with a mature cystic teratoma autoamputated into the cul-de-sac and subsequently diagnosed by laparoscopy.