There are many reasons for the appearance of dark spots on the lips. The common one is the deposition of melanocytes. Generally, when black spots appear on the lips, there is no special pain and other symptoms. Often when you look in the mirror, you find that black spots appear on the lower lip, which can easily attract people’s attention. It is best to visit the mucous membrane department of a dental hospital and review it regularly. There is also a systemic disease that can have lip pigmentation called hyperpigmented polyp syndrome, which is an autosomal dominant disorder. It is characterized by dark pigmented spots on the oral mucosa, perioral skin and other areas, multiple polyps in the gastrointestinal tract, and runs in families. Hyperpigmentation is one of the main signs of the disease, most often appearing around the mouth and lips. The damage is black, brownish-black, brown, flat, not elevated, scattered or clustered, often 1-5 mm, round, oval, sometimes symmetrical, and usually appears first on the red part of the lips around the mouth than on the skin. With age, the pigmentation spots can increase in size, number and color, and sometimes the dark spots become lighter or disappear in adulthood. Therefore, if a child is found to have dark pigmented spots on the perioral skin, he or she should be advised to visit a gastroenterologist to detect multiple polyps in the gastrointestinal tract.