Peutz-Jeghers syndrome is a rare autosomal dominantly inherited condition, characterized by the presence of hamartomatous gastrointestinal polyps and mucocutaneous pigmentation. Patients with this syndrome can be associated with other neoplasms such as ovarian neoplasms known as sex-cord tumor with annular tubules that are associated in one third of the cases with this syndrome and other types of malignancies. We report a 42-year-old woman with a history of Peutz-Jeghers Syndrome and bilateral breast cancer that presented with abnormal uterine bleeding. Total abdominal hysterectomy with bilateral salpino-oophorectomy was done and an ovarian sex cord tumor with annular tubules was incidentally diagnosed. By reviewing literatures and in agreement with previous studies we suggest routine screening for malignancies in patients with Peutz-Jeghers syndrome.