Precocious puberty refers to the early onset of puberty, that is, the appearance of gonadal enlargement and secondary sexual characteristics before the age of 8 in females, or the appearance of menstruation before the age of 10, and the development of males before the age of 9. According to the different pathogenesis, precocious puberty can generally be divided into two categories: gonadotropin-releasing hormone (GnRH)-dependent precocious puberty (true precocious puberty) and non-GnRH-dependent precocious puberty (pseudo-precocious puberty); the former is called central precocious puberty or complete precocious puberty, and the latter is called peripheral precocious puberty. In addition, incomplete precocious puberty, such as simple premature breast development and simple premature pubic hair, is classified as a variant type of puberty by some scholars.