Ovarian pregnancy is very rare and to our knowledge, no case has been reported in Cameroon. We herein report a case at the Yaounde Central Hospital. It is the case of a 29 years old woman who consulted in emergency for left pelvic pain at 9 weeks of pregnancy. The level of beta human chorionic gonadotropin was 96702 milli-international Units/ milliliter and ultrasound revealed an intra-ovarian gestational sac, an empty uterus and no peritoneal effusion. In the absence of facilities for laparoscopy, an emergency laparotomy was done. We found the non ruptured mass inside the left ovary. The left fallopian tube, the uterus and the right adnexae were normal. We did a successful ovarian dissection and resection of gestational sac. Trophoblastic tissue was found at pathology. Similar symptoms should draw attention of practitioners on the plausibility of ovarian pregnancy.