Scalp is very dry, usually with excessive cleaning, dry seborrheic dermatitis, micronutrient deficiencies and other factors related to the cause can be based on the cause of good daily care, if necessary, need medication. 1. Excessive cleaning: part of the population is relatively clean, long-term excessive cleaning of the scalp may make the scalp repeatedly stimulated, easy to cause scalp dryness, usually need to reduce the appropriate number of cleaning, reduce the stimulation of the scalp. 2. Dry seborrheic dermatitis: a kind of seborrheic dermatitis, related to inflammation and infection, when the inflammation repeatedly stimulate the scalp, may lead to dry skin, itching. When serious, it is easy to cause dandruff. Treatment should pay attention to scalp hygiene, reduce secondary infection, severe symptoms can be applied tacrolimus ointment, pimecrolimus and other drugs. 3. Micronutrient deficiency: prolonged lack of vitamin A may lead to dry skin, manifested as facial dryness, hand dryness, scalp dryness, etc., can be found through the micronutrient screening, the lack of which should be supplemented in a timely manner, such as oral vitamin A and so on. If the scalp is abnormally dry and there is dandruff, it may also be due to a long-term lack of moisture, it is recommended to drink more water to ensure adequate moisture. If you need to use drugs, should be under the guidance of a professional physician, do not take without authorization.