A mole on the back, generally referred to as melanocytic nevus, is a benign skin tumor of melanocyte origin, which generally does not require special treatment. If it feels that it affects aesthetics, it can be removed by chemical corrosion, electrocautery, surgery, etc. Those with malignant tendency should be excised as early as possible and histopathological examination should be done at the same time. Nevus can be divided into congenital and acquired, the skin lesions are flat or slightly elevated macules or papules, also can be papillomatous, wart-like, nodules or damage with tips, the surface is smooth, may or may not have hair, and the number varies. According to the depth of nevus cells, nevus cell nevus can be categorized as junctional nevus, compound nevus and intradermal nevus. If there is no discomfort, no special treatment is needed. If you feel that it affects your beauty, you can go to the dermatology department of the hospital and take the doctor’s advice to treat it. For example, corrosion by corrosive drugs and treatment by electrocautery can remove epidermal nevus by cauterizing and charring. When the pigment of nevus deepens and becomes bigger, or when there is itching and pain, it is possible for malignant transformation, so it should be done complete excision in time and sent for pathological examination. If there is ulceration and bleeding, it should be more vigilant. To summarize, most of the pigmented nevi on the back are benign lesions. If you find that the pigmented nevus becomes bigger, darker, itchy and painful, it is recommended to go to the hospital in time, and if necessary, carry out pathological examination to understand the nature of the nevus.