An ovarian sex-cord tumor with annular tubules (SCTAT) and with Charcot-Böttcher bodies in a 29-year-old woman with primary infertility, secondary amenorrhea, and without evidence of the Peutz-Jeghers syndrome was studied by light and electron microscopy. At laparotomy, a right ovarian tumor was removed, and there was no evidence of metastases. The patient has been well and disease free for a period of 3 months after surgery. The tumor was histologically composed of nests of cells arranged in complex tubules with hyaline bodies. Ultrastructurally, cells were joined by specialized junctions along their lateral adjacent borders. Microvilli and cilia were absent. Concentrically arranged membranes were seen in the cytoplasm. Charcot-Böttcher filaments were seen in paranuclear region. The findings of Charcot-Böttcher filament in an ovarian SCTAT support the hypothesis of the Sertoli nature of this neoplasm.