Lips purple black may be due to climatic factors, lung disease, individual differences and other reasons, the specific causes should also go to the hospital in a timely manner to confirm the examination. 1. Climatic factors: in winter, if you are in a warm environment for a long time, and do not do a good job of keeping warm when you go out, it will slow down the blood circulation, when the blood stays in the lips for a long time, it will cause the phenomenon of purple and black lips. 2. Lung disease: when the lung disease, such as: chronic bronchitis, lung infection, pulmonary insufficiency and other symptoms, so that the lung function decline, will make the body hypoxia, will lead to cause the symptoms of purple and black lips. 3. Individual differences: some people are born with deeper lip color, can be black for this, such as no discomfort symptoms, no treatment. Lips caused by more causes, when the body appears uncomfortable symptoms, it is recommended to go to the hospital in time for diagnosis, as soon as possible for targeted treatment.