Background: Yolk-sac tumors of the ovary (YSTs) are rare, highly malignant tumors that affect mostly children and young adults. Prognosis of YST is worse than for other malignant ovarian germ-cell tumors and is strongly correlated with stage of disease. Case: A 23-year-old female presented with fever, malaise, lower abdominal pain, and distension. An ultrasound examination revealed a solid tumor with a cystic area arising from the left ovary. A left salpingo-oophorectomy with an omentectomy and multiple biopsies of the pelvic and abdominal peritoneum was performed, because a malignant stromal tumor was found during frozen-section examination. Pathologic examination revealed a mature cystic teratoma and a yolk-sac tumor in the left ovary, with a metastatic focus in the resected part of the omentum. Results: This patient conceived 2 years after surgical treatment and adjuvant chemotherapy and delivered a healthy male baby. During 11 years of follow-up, there was no recurrence of the tumors. Conclusions: Given that radical surgery does not seem to improve survival and considering high the chemosensitivity of YSTs, fertility-sparing surgery may be a reasonable option for women in reproductive age with advanced-stage YSTs of the ovaries. (J GYNECOL SURG 30:357)