”Mole”, also known as pigmented mole, is actually what we usually call a black mole or nevus. Pigmented nevus is divided into congenital and postnatal, which can be present at birth, but often occurs after 2 years old, with a large or small number, slow progress, no conscious symptoms, and mostly yellow, brown or black color, but also blue, purple or colorless. According to the location of nevus cells in the skin, they are divided into three types: junctional nevus, mixed nevus and intradermal nevus. 1. They are generally smooth and hairless, and can occur on any part of the body, and can occur in both men and women. Most often occurs in the mucous membrane of the palmoplantar and genital areas; 2. Mixed nevus: slightly higher than junctional nevus and may occur all over the body; 3. Intradermal nevus, the most common type of nevus in adults. It can occur in any part of the body, ranging from a few millimeters to a few centimeters in size, with regular edges and different shades of brown color, with hair on the surface, slightly thicker than normal hair, in a hemispherical elevation, or papilloma-like or with a tip. The typing of pigmented nevi must rely on histopathology and is difficult to determine by visual observation alone. Although most of us have moles on our bodies, the probability of cancerous changes is very small. What kind of moles are more likely to develop malignant changes? Clinical studies have found that junctional moles are more likely to develop malignant changes. However, pigmented moles on the palms of the hands, soles of the feet, genitals, under the nails, fingers, toes and mucous membranes should be carefully avoided, because repeated and excessive stimulation often has the risk of turning into malignant melanoma. In daily life, once a pigmented nevus appears in the following cases (except during sexual maturity or pregnancy), timely removal should be considered: ① sudden increase in size and area, rough surface; ② redness around the nevus or sudden darkening, color deepening, depigmentation and hair removal; ③ surface erosion, exudation, bleeding, ulceration and swelling; ④ self-conscious pain or itching; ⑤ satellite foci similar to the original pigmented nevus appear around it, i.e., pigmented nevus (6) Enlarged lymph nodes around the nevus; (7) New nevus in the elderly. (8) If the nevus occurs in the palmoplantar, waist, axilla, shoulder, groin and other friction-prone areas, even if there are no such changes, it should be considered for elective removal. Treatment methods include surgical excision, laser, electrocautery, freezing, drug erosion, etc. However, surgical excision is generally advocated to avoid repeated stimulation by other therapies, which may lead to malignant changes. Surgical excision can not only completely remove the lesion, but also make histopathological examination at the same time to clarify the diagnosis and leave no future problems. Of course, the choice of treatment method should be determined according to the purpose of treatment, the location, size and number of pigmented nevi, but for those with scarring body, especially when it occurs on the face, caution should be exercised.