The indications for CO2 laser in dermatology are warts, soft fibroids and seborrheic keratosis, pigmented nevi and so on. 1. Warts: etiologically speaking, they are caused by skin infected with human papilloma virus (HPV), with the appearance of slightly raised, flat-topped pimples, the color of light brown, pink or normal skin color, and are often densely packed in groups or scattered in many places. It can be physically treated by carbon dioxide laser. 2. Soft fibroma: single pocket type, occurring in the lower part of the trunk, is a single pocket-shaped swelling, the root is thin, tibial, soft to the touch, inelastic, normal skin color. Smaller skin tags can be removed or cut off, and can also be treated with electrocautery, freezing, carbon dioxide laser and other cauterization. 3. Seborrheic keratosis: long-term bad habits, endocrine system disorders; this condition usually has no obvious conscious symptoms; it can be treated by laser or surgery. 4. Pigmented nevus: a benign tumor formed by proliferation of melanocytes. It can be removed by carbon dioxide laser or surgery. However, if the nevus is malignant, surgical excision and histopathological biopsy are needed. After surgery, keep the wound clean and dry, and avoid water for 3-7 days. The surrounding skin can be cleaned with a wet towel. After the wound in the exposed area is scabbed off, avoid sunlight exposure or apply sunscreen to prevent hyperpigmentation.