Fractional laser treatment for acne pits varies from person to person, and results can usually be seen about 3 months after treatment. Acne pits, or depressed scars, may remain after the acne has healed. Fractional laser can stimulate the bottom of the depressed scar through the photothermal effect of laser to promote the rearrangement of collagen fibers and stimulate collagen regeneration to improve the appearance of acne marks. Fractional laser treatments can be categorized into two types of lasers: peeling lasers and non-peeling lasers, which do not damage the local skin at all, and the recovery time will be different as well. Peeling fractional laser will have symptoms of swelling and bruising in the early stage, and the wound healing time is longer, while non-peeling fractional laser is less traumatizing and heals faster, but it takes 3 months to improve the appearance more obviously. If proper care is taken, there is usually improvement with each treatment, and multiple treatments are needed to achieve the ideal visual appearance, with the number of treatments depending on the severity of the pimples. On the other hand, fractional laser is an invasive laser operation, which has higher requirements on equipment and operators, so it is recommended to choose dermatology or cosmetology department of regular medical institutions for treatment.