Laser treatment can be used to treat a wide range of skin problems. It is an effective physical treatment and the most common cosmetic treatment today, whether or not the method will leave scars depends on a number of factors, such as the type of laser, the mode of treatment, the depth of the energy and whether or not you are a scarred person. Laser treatment usually does not leave scars because different wavelengths of laser light can selectively absorb black, blue, brown and other pigments in the skin. The small spot area of the laser and the very short time that the laser beam passes through the skin in milliseconds and microseconds cause very little thermal damage to the epidermis, which is also the reason why the epidermis does not leave scars. However, for people with scarred body, there is a higher chance of scarring after laser treatment, so they need to choose carefully. Laser treatment is commonly used in freckle treatment, freckle is epidermal pigmentation disease, laser freckle only damage epidermal pigment, will not damage other areas of the epidermis and dermis area, generally will not leave scars; mole treatment may leave scars or in the informal health care institutions to carry out high-intensity photorejuvenation may also leave scars. In addition, after laser treatment, we should do a good job of local skin care, if there is redness, swelling, pain, you can use ice packs, frozen masks for instant ice to relieve, avoid washing within 3 days, while avoiding intake of stimulating foods, tobacco, alcohol, so as not to cause infection, leaving postoperative scars.