Darkening of the nose may be related to localized trauma, melanosis or prolonged sun exposure of the nose. Melanosis, also known as melanosis, is a diffuse hyperpigmented skin disease that occurs on the face and neck. Typical symptoms are dark brown or blue-gray patches on the forehead, behind the ears and around the nose, accompanied by small pigmented spots around the hair follicles. If there is a history of trauma to the perinasal area, deepening of the color of the perinasal skin and hyperpigmentation may also be present during the scabbing period of the wound. When the perinasal area is exposed to ultraviolet light for a longer period of time, it can lead to the synthesis of more melanin by local melanocytes to absorb ultraviolet light, which leads to localized melanin deposition in the perinasal area, manifesting itself as darkening of the perinasal area. There are other reasons for the darkening of the nose, such as the discovery of the presence of melanin around the nose skin, should promptly consult a doctor, do not take the initiative to deal with, in order to avoid delays in the condition. Avoid prolonged sun exposure on weekdays, quit smoking and drinking, and keep a regular routine.