The whitening of the corners of the mouth may be a precursor to vitiligo, but it may also be caused by diseases such as pityriasis alba and albinism. 1. Vitiligo: The onset of vitiligo is mostly related to heredity, autoimmune system disorders and other factors, leading to a decrease in the production of melanin, and the patient’s skin will appear white spots. If the corners of the mouth are white, it may be a sign of vitiligo. 2. white chaff rash: the cause of this disease is not yet clear, may be related to pathogen infection, malnutrition, sun exposure and other factors may also trigger the disease. The disease is common in the face, the patient’s skin will appear round, oval pale color spots. 3. Albinism: The cause of albinism is mostly related to heredity and other factors, and patients will have symptoms such as snow-white or pink skin. If you have albinism, you may experience whitening at the corners of your mouth. The cause of the whitening of the corners of the mouth is not unique, and it is recommended that patients go to a regular hospital to clarify the cause of the disease.