Baldness is a manifestation of alopecia, specifically seborrheic alopecia, pathogenic infections, systemic diseases and many other reasons, need to be specifically analyzed. 1. Seborrheic alopecia: if the patient has an increase in androgen secretion, it will make the hair follicles of oil secretion caused by hair loss, this disease often has a family history of autosomal dominant heredity, and the patient’s father and brother also often have the symptoms of seborrheic alopecia. 2. Infection by pathogens: If the local hair follicles are infected by pathogens such as bacteria or fungi, it may destroy the hair follicles, resulting in inactivity of the hair follicles, which prevents the hair from growing. 3. Systemic diseases: For example, conditions such as systemic lupus erythematosus, syphilis, and abnormal thyroid function can affect the local metabolism of the scalp, resulting in hair loss. In addition, drugs may also lead to hair loss, if the symptoms of hair loss is serious, it is recommended to go to the hospital in time to get medical treatment, to clarify the cause of hair loss, and take a reasonable way of treatment.