The causes of hair on pubic bone are divided into physiological and pathological, physiological hair on pubic bone is related to heredity and other factors, pathological causes are related to hirsutism, polycystic ovary syndrome and other diseases. 1. Physiological factors: a lot of hair on the pubic bone may be related to heredity, if the parents have a lot of hair on the pubic bone, their children have a lot of hair on the pubic bone will increase the chances of hair on the pubic bone. 2. Hirsutism: the cause of the disease is more complex, may be androgen levels, external stimulation, drug effects and other factors. Clinical manifestations are that a large number of hairs appear in areas that should not have hair, or localized and generalized hairs that are thicker, longer and more hairs than normal, and some patients will have a lot of hairs on the pubic bone. 3. Polycystic Ovary Syndrome (PCOS): The cause of the disease may be related to genetic and environmental factors, and it manifests itself in symptoms such as menstrual disorders, hirsutism, acne, infertility, etc., and it is mostly found in the groin, the middle line of the lower abdomen, and the inner side of the thighs. There is no single reason for a lot of hair on the pubic bone. After excluding physiological factors, patients are advised to seek medical examination to clarify the cause.