From a cosmetic point of view, skin aging is mainly focused on three aspects: texture, color, and delicacy. Specifically on the face, skin aging can be manifested as skin laxity, lack of elasticity, wrinkles, dull color, enlarged pores, capillary pore openings, and various pigment spots. Skin aging can have a variety of complex causes, but two factors are the most important. That is: endogenous skin aging and exogenous skin aging. 1, endogenous skin aging As people grow older, their own metabolic ability gradually decreases. Under normal circumstances, the dermal connective tissue matrix contains 70% of collagen, which determines the strength of skin tension, and 2%-4% of elastic tissue, which determines skin elasticity and resilience. The rate of collagen loss in adults is approximately 1% per year over a lifetime. The amount of elastin lost is less precise, but its amount decreases significantly after the age of 28. In addition, collagen bundles become progressively thinner with age and may change to a few loosely woven tangled or straight fibers. The final result is the inability to maintain the integrity of the dermal structure, thus causing a significant decline in skin texture and quality. 2.Exogenous skin aging mainly includes the physiological and functional changes of the skin caused by long-term ultraviolet radiation, bad climate and environment, bad living habits and excessive work stress. Photoaging of the skin is the largest part of exogenous aging. It is caused by repeated exposure to ultraviolet rays and is characterized by changes in skin morphology and function similar to physiological aging, mainly manifested by roughness, laxity, atrophy, lack of elasticity and luster, deepening and thickening of wrinkles, blotchy pigmentation, capillary dilation, purpura, etc. In the past decades, skin rejuvenation treatment has undergone a giant change in terms of awareness concept and treatment method (rejuvenation). In fact, physical methods such as ultrasonic atomized cold spray, intermediate frequency electrical stimulation, and infrared physical therapy have been used for cosmetic treatments for a long time. Later, mechanical grinding and chemical peeling methods were used. These methods do make some improvements to the epithelium, but they are complicated to operate and have many postoperative side effects and risks. They have limitations in tightening the skin, improving skin microcirculation and promoting skin absorption, so they cannot be widely carried out and accepted. How to achieve skin rejuvenation (skin rejuvenation) effectively and safely is one of the topics that have been explored in cosmetic dermatology and aesthetic surgery. In the last decade of the 20th century and the first decade of the 21st century, with the advancement of laser technology, lasers have shone in the field of non-invasive or minimally invasive cosmetic treatments, providing more options for skin rejuvenation.