Picosecond laser surgery is to act on the skin through strong electric pulse to break up and shatter the melanin under the skin, and then the melanin is discharged out of the body through lymphatic circulation, so as to achieve the purpose of removing spots, repairing wrinkles, repairing acne pits, and repairing scar tissues and so on. However, picosecond laser surgery can also cause the following surgical risks: 1, pain and discomfort: the slight stinging sensation during laser treatment can be generally tolerated, for pigmented diseases and skin vascular diseases, local anesthesia can reduce the discomfort; 2, skin swelling: the laser beam directly reaches the epidermis of the skin, which will stimulate some sensitivity factors and lead to skin swelling, generally one week can reduce the swelling; 3, skin dryness: the use of picosecond 3, skin dryness: the use of picosecond technology to remove pigmentation at the same time, will accelerate the skin cell division, differentiation, the face needs a lot of water, the skin will appear dry, tight, and even flaking phenomenon; 4, erythema: most of the laser treatment surgery, the immediate appearance of erythema reaction, after the thermal reaction subsides, erythema can also be eliminated. After the erythema subsides in some patients, the manifestation of hyperpigmentation will be shown, and corresponding treatment can be given according to hyperpigmentation; 5. Infection: the incidence of infection in the operated area after laser treatment is not high, which occurs mostly in the larger and moist traumas, and scar will be formed after the occurrence of infection; 6. Abnormal pigmentation: if the frequency of operation and the use of inappropriate parameters, it will lead to pigmentation or reactive pigmentation, such as chloasma.