Introduction: Ectopic pregnancy is a serious health problem that leads to maternal mortality and morbidity. The current article was based on the record of a female patient with primary ovarian ectopic pregnancy. Case Presentation: The patient was a 28-year-old female with regular previous menstrual cycle and without using any contraception method. She presented with right lower abdominal pain and amenorrhea. Transvaginal sonography findings revealed a gestational sac in the right ovary. Finally, primary ovarian ectopic pregnancy was diagnosed by laparotomy and confirmed by histopathology. Conclusions: To prevent misdiagnosis, an awareness of this issue should be developed by gynecologists, surgeons, and radiologists.