1, idiopathic precocious puberty, also known as somatic precocious puberty, is caused by the hypothalamus’ decreased sensitivity to the negative feedback of sex hormones, resulting in premature secretion of gonadotropin-releasing hormone, which is more common in females, accounting for more than 80% of girls’ CPP, while only about 40% of boys. 2.Precocious puberty secondary to abnormalities in the central nervous system, including: ① tumors or occupying lesions: hypothalamic malformations, cysts, granulomas, ② central nervous system infections, ③ acquired injuries: trauma, post-operative radiotherapy or chemotherapy, ④ developmental abnormalities: hydrocephalus, optic septal hypoplasia, etc. 3, other diseases primary hypothyroidism. 4.Gonadal tumors Ovarian granulosa-vesicular membrane cell tumor, luteinoma, testicular mesenchymal cell tumor, teratoma, etc. 5, adrenal gland diseases adrenal tumors, congenital adrenal cortical hyperplasia, etc. 6.Exogenous Such as estrogen-containing drugs, food, cosmetics, etc. 7.Simple premature breast development, simple premature pubic hair development, simple premature development.