Ovarian cancer accounts for approximately 22,000 cases annually in the United States. Although the vast majority of ovarian cancers occur in postmenopausal women and are of advanced stage, a significant subset occurs in young women. Among those subtypes having a predisposition for young women are malignant ovarian germ cell tumors, sex cord-stromal ovarian tumors, and tumors of low malignant potential. However, invasive epithelial ovarian cancers may also occur in young women, particularly the subtypes of low-grade serous carcinoma and mucinous carcinoma. This article details the diagnosis and optimal treatment of ovarian cancers subtypes in young women.