Juvenile granulosa cell tumor (GCT) of the ovary is a rare neoplasm occurring in premenarchal girls and young women. Juvenile GCT that occurs in premenarchal girls usually produces sexual precocity as a consequence of estrogen secretion. Juvenile GCTs are more likely to grow to a relatively large size with a much smaller likelihood of peritoneal spread, unlike their counterpart, epithelial ovarian neoplasms. We report the radiology and pathology of a patient with juvenile GCT and review the literature of this rare tumor.