Hair black thick hard reason usually mainly include congenital genetic factors, cleaning improper factors, once found, need to timely medical treatment. 1. congenital genetic factors: hair distribution in the human scalp, generally by the scalp outside the hair shaft and scalp inside the hair bulb, hair roots, hair papillae, etc., hair black coarse hard hair exposed outside the hair cadres bit thick and black and hard, some people’s hair is born with dry hair, resulting in a lack of moisture and oil in the hair shaft, so it can be manifested as hair black coarse hard. 2. Improper cleaning: excessive hair cleaning or alkaline shampoo shampoo, often do beauty programs will damage the hair structure leading to dry hair, the lack of moisture and grease in the long run, can be manifested as hair dry, black, thick and hard. Patients can usually use mild shampoo to wash their hair, avoiding the use of alkaline shampoos or various beauty programs such as perming and hair coloring. If necessary, actively consult the doctor and standardize the treatment under the doctor’s guidance.