Primary ovarian pregnancy is one of the rarest varieties of ectopic pregnancies. Patients frequently present with abdominal pain and menstrual irregularities. Preoperative diagnosis is challenging but transvaginal sonography has often been helpful. A diagnostic delay may lead to rupture, secondary implantation or operative difficulties. Therefore, awareness of this rare condition is important in reducing the associated risks. Here, we report a case report of ovarian pregnancy presented. A 29-year-old woman, nulliparous, was admitted to the hospital forsuspected ectopic pregnancy. A transvaginal sonography failed to hint at ovarian ectopic. She was successfully managed by surgery and histological studies confirmed an ovarian pregnancy.