More and more melanin on the face may be related to physiological factors such as ultraviolet radiation, or pathological factors such as acanthosis nigricans and chronic hepatitis. 1. Physiological factors: common causes such as ultraviolet radiation, if the human body for a long time in the sun, ultraviolet radiation can trigger a large number of melanocytes proliferation, activation, melanin production, so the phenomenon of increased melanin. 2. Pathological factors (1) Acanthosis nigricans: often due to heredity, obesity and other reasons lead to deepening of skin color, skin folds appear wart-like cumbersome organisms, so the phenomenon of increased melanin can appear on the face. (2) Chronic hepatitis: liver cell damage caused by various reasons, so that the detoxification function of the liver decreases, the patient can appear liver disease face, manifested as yellowish skin sclera, dull and lusterless skin, the face can appear melanin deposition, so the phenomenon of increasing melanin on the face. Melanin on the face more and more may also be caused by other diseases, it is recommended that patients go to the hospital in a timely manner to clarify the diagnosis, under the guidance of the doctor standardized treatment.