A little girl, 6 years old, was brought to the Flower Season Care Center by her mother because of breast pain and was diagnosed with precocious puberty after examination. In recent years, the incidence of precocious puberty in girls has been on the rise. However, if detected in time, most children with precocious puberty can be effectively controlled through active treatment. Therefore, it is especially important to have information about precocious puberty. The following information can help early detection of precocious puberty in girls: before the age of 8, the development of breasts, the growth of axillary hair, the development of vulva, the appearance of pubic hair, the coloring of labia (darkening), the increase of vaginal discharge, the onset of menstruation in girls under the age of 10, and the sudden acceleration of height growth in children before the age of 10 is also a sign of precocious puberty. Breast development can occur in normal girls after the age of 8. The breast has a development process from small to large, can start to appear on one side, but also both sides at the same time, these are not abnormal; when found after the daughter 10 weeks of age menstruation, there is no need to be nervous, this belongs to the normal range. Physical examination information includes: 1, general examination including height, weight, breast, armpit hair, external genital examination. 2.B ultrasound examination B ultrasound is one of the routine examination methods to diagnose precocious puberty, which can detect breast development and identify breast inflammation or tumor; the development of uterus and ovaries, and the presence of diseases of internal reproductive organs; in addition, it can also detect adrenal tumor related to precocious puberty. According to the level of hormone, the cause of precocious puberty or the site of lesion can be inferred. In precocious puberty, the bone age index is very important. The bone age determined by X-ray is more than 2 years earlier than the actual age, and the bone age of pseudoprecocious puberty matches the age, while the bone age of about 95% of children with true precocious puberty is earlier. 5, if necessary, can also do cranial CT or magnetic resonance imaging (MRI) examination, in order to exclude intracranial tumors.