There are a variety of reasons for the blackness around the lips, which may be related to lipitis, melanosis, hypoxia and ischemia, food poisoning and so on. 1. Lipitis: long-term outdoor work, wind and sun exposure, contact with cosmetics or drugs and other stimulation of local tissues, can cause pigmentation, the edge of the lips black, or swelling, oozing and other phenomena. 2. Melanosis: long-term exposure to photosensitive substances, coal tar can lead to local skin, mucous membrane hyperpigmentation. 3. Hypoxia and ischemia: such as pulmonary insufficiency, pulmonary hypertension or chronic pulmonary heart disease, emphysema and other lung diseases caused by insufficient oxygen supply to the body, or myocardial ischemia, heart failure and other heart disease patients with insufficient blood supply to the tissues of the body, there will be a blackened lips around the performance. 4. Rare cases: such as chemicals or food poisoning, the body lack of oxygen after the hemoglobin will be compensatory increase resulting in blackness around the mouth. It is recommended that patients appear black around the lips timely to the regular hospital examination, clear reasons, reasonable standardized treatment.