Undescended ovary is a rare entity and usually presentedas a case report. It is associated with urinary and uterine anomalies. Symptomatic patients are diagnosed during surgery. Most of the patients are asymptomatic and treatment is unnecessary. They are incidentally diagnosed during infertility evaluation and treatment such as ovarian hyperstimulation studies. A 15-year-old female patient presented with the diagnosis of renal cystic massas identifiedduring ultrasonography in another hospital. Abdominal computedtomography image was requested. A cystic lesion of about 48×34 mm with well-defined borders associated with the appendix and probably with mucocele of the appendix was reported in the lower right abdominal quadrant close to the cecum. During exploration, the right ovary was seen to be attached to the cecum and was higher in position as well as a right ovary originated cystic structure of 5×5 cm. Using needle aspiration, intraovarian hemorrhage was confirmed and partial cystectomy was performed. The present study reports on an undescended ovary that hadacute abdomen symptoms imitating mucocele. In girls referring to the hospital with abdominal pain, although quite rare, undescended ovaries are to be also considered. As the incidence of renal and uterine anomalies is higher in suchpatients, in symptomatic cases relevant organs are to be investigated carefully during surgical intervention.