The female top hair is too thin may be related to genetic factors, mental stress, endocrine dysfunction, malnutrition, skin disease, chemical factors, drug factors and other reasons, patients should be based on their own situation for preliminary identification, but also can consult a doctor. 1, genetic factors: if the parents top hair is too thin, that may also lead to the child too thin top hair situation, men generally more in 20 -30 years old occur, while the female to 60 years old patients; 2, excessive mental stress: in the fast and intense pace of life and work and fierce social competition, people may be under great mental stress, resulting in thinning hair on the top of the head or even fall off; 3, endocrine dysfunction: endocrine gland function abnormalities, will cause hormone imbalance in the body, resulting in thinning hair on the top of the head, and even hair loss, common in Postpartum, menopausal population, also seen in hyperthyroidism, hypothyroidism, hypopituitarism and other endocrine diseases; 4, malnutrition: such as a reduction in food protein intake can delay hair production; fat intake will cause too thinning hair on top of the head; intake of vitamin A, vitamin B and minerals such as zinc, iron and other inadequate, will also lead to a lack of nutrients in the hair follicle caused by dry, thinning hair; 5, skin diseases : girls suffering from dermatological diseases such as ringworm, balding folliculitis, carbuncle, exfoliative dermatitis, etc., can have thinning hair on the top of the head, or may be suffering from seborrheic alopecia, should be based on the condition, a clear diagnosis, according to the specific disease to give treatment; 6, chemical factors: most tumor patients after receiving radiotherapy will have thinning hair, hair loss, this belongs to the temporary; 7, drug factors: after taking After taking certain drugs, hair may fall out to different degrees, which will lead to hair thinning and baldness, these drugs include anti-tumor drug colchicine, anti-TB drug ethambutol, etc.