Objective: Unusual setting of medical care. Background: A yolk sac tumor (YST) is a rare, malignant tumor of cells that line the yolk sac of the embryo. It most frequently occurs in the ovary (ovarian yolk sac tumor: OYST) in children and adolescents. Thus, fertility-preservation treatment is a concern. Case Report: A 24-year-old nulliparous woman visited us for infertility treatment and then right OYST was detected. A unilateral right salpingo-oophorectomy, infra-colic omentectomy, ipsilateral lymph node dissection, and peritoneal biopsies were performed. Histological examination confirmed the diagnosis of a stage IC OYST. Six cycles of bleomycin-etoposide-cisplatin chemotherapy were performed. She had no recurrence over the next 16 months. She conceived by in-vitro fertilization, and abdominally gave birth to a term infant. Both mother and baby had a smooth recovery. Conclusions: This case adds further evidence to the 5-year survival and progression-free survival following surgery and chemotherapy in OYSTs, while preserving fertility. [ABSTRACT FROM AUTHOR]