Teratoma refers to a common type of germ cell tumor, which can be classified into mature teratomas and immature teratomas. Mature teratomas are benign tumors, accounting for 10%-20% of ovarian tumors. They can occur at any age but are more common between the ages of 20 and 40. Most are unilateral, of moderate size, and usually have a single compartment filled with sebum and hair; sometimes teeth and bone can also be found. Immature teratomas, on the other hand, are malignant tumors, making up 1%-3% of ovarian teratomas. These are more frequent in younger patients, with an average age of 11 to 19 years. The ovaries are predominantly solid but may include cystic areas, primarily consisting of primitive neural tissue. The malignancy level of the ovary depends on the proportion of immature tissue, the degree of differentiation, and the content of neuroepithelial tissue.