OBJECTIVE: To describe the treatment of a 23-year-old patient with primary peritoneal carcinoma and preservation of her fertility. DESIGN: Case report. SETTING: University of Schleswig-Holstein, Campus Lübeck, Department of Gynecology and Obstetrics. PATIENT(S): A 23-year-old patient with primary peritoneal carcinoma. INTERVENTION(S): The patient was given treatment by first preserving her fertility with oocyte vitrification and cryoconservation of ovarian biopsy samples. Surgery was performed with radical resection of the peritoneal lesion, ovarian biopsies, omentectomy, and pelvic and para-aortic lymph node sampling before starting chemotherapy with carboplatin and paclitaxel (Taxol). Hysterectomy and bilateral salpingo-oophorectomy were not performed. MAIN OUTCOME MEASURE(S): Treatment of peritoneal carcinoma and number of vitrified oocytes. RESULT(S): Twenty-five oocytes of the patients were vitrified before chemotherapy was performed. CONCLUSION(S): Primary peritoneal carcinoma is a rare disease that laparoscopically resembles peritoneal endometriosis and histologically is very similar to primary epithelial ovarian cancer. The advised therapy is based on ovarian cancer treatment; however, it is unclear whether the radical operation improves prognosis. In this case, a 23-year-old patient underwent treatment preserving her fertility with oocyte vitrification and cryoconservation of ovarian biopsy samples before surgery and chemotherapy were performed.