With the introduction of the concept of selective photothermal action in 1983 and the emergence of new cosmetic devices represented by pulsed lasers, cosmetic lasers, a new medical aesthetic technology, have gained widespread attention and popularity worldwide and have rapidly conquered all dermatologists and beauty lovers. Laser is a high-energy coherent monochromatic light that can be focused into a very small spot and act on the skin tissue, generating considerable heat in the local lesion to achieve the purpose of destroying the target structure. Lasers are used for a wide range of applications, including the treatment of abrasion, vascular lesions, pigmented lesions, tattoos, hirsutism, and photoaging skin. In the treatment of skin lesions, pulsed laser can selectively remove specific skin structures such as blood vessels, melanin vesicles and hair follicles with little to no involvement of surrounding tissues and minimal damage to normal skin tissues, making it particularly suitable for cosmetic dermatological treatments. Pulsed lasers are divided into two major categories: exfoliative and non-exfoliative. The ultra-pulsed CO2 or pulsed Er:YAG lasers are representatives of the exfoliative lasers. Both are strongly absorbed by water and can grind superficial skin lesions with a controlled, precisely focused beam, causing mild damage. Dermabrasion is very effective for photoaging, scars, pigmented nevi, warts, skin tags and seborrheic keratosis (age spots). Ultra-pulse CO2 still has obvious hemostatic effect and no suture is needed after surgery, which has incomparable advantages over traditional surgery in treating eye bags. The theory of focal photothermal action, which emerged in 2003, has added fractional treatment to this type of laser. The fractional laser treatment mode is to produce evenly distributed small pinhole-sized wounds in the irradiated area, leaving a small area of skin unaffected, so the postoperative recovery is fast and safe. After 3 or more treatments, the results of scar removal, wrinkle removal and skin tightening can be achieved, which is widely welcomed by cosmetic patients. Non-ablative lasers are more common, such as pulsed dye, alexandrite, semiconductor laser, etc. Other light sources or technologies such as intense pulsed light (IPL), electroporation also belong to this category. The pulsed dye laser is mainly absorbed by the oxygenated hemoglobin in the skin blood vessels, resulting in serious destruction of blood vessels, which is a revolutionary leap in the history of vascular lesion treatment as it is effective in the treatment of nevus, leaving almost no side effects and excellent overall performance. Vitreous oxide and other lasers perform very well in pigmentation diseases, such as nevus of Ota, cheekbone nevus, freckles and age spots, and refractory pigmented lesions such as coffee spots and freckle-like nevus can be cleared up, and there are no obvious side effects, so that no new technology can replace them for more than 10 years. Semiconductor and other long pulse laser can selectively heat, destroy the hair follicle, treatment of various reasons caused by excessive hair efficacy, safe and reliable, is the current hair removal method of choice, for many female patients to lift the summer troubles. In the past two years in China, the electric wave facelift is very popular, it is actually a radio frequency technology, different from plastic facelift and named, mainly for the treatment of skin wrinkles and laxity. The treatment principle is to stimulate the skin dermis through radiofrequency energy, so that collagen tissue contraction, and let the collagen continue to grow, orderly restructuring arrangement, tighten the skin, fill in the wrinkles, regain the skin’s firmness and smoothness. Intense pulsed light is a new pulsed technology for beauty care that became popular after 1995, also known as photorejuvenation in China, which has a definite effect on some superficial pigmentation and vascular lesions of the facial skin, as well as early skin wrinkles and laxity. The principle of pigmentation and vascular treatment is the same as the corresponding pulsed laser, while skin rejuvenation and wrinkle removal is similar to electroporation. Photorejuvenation has no damage after the procedure and requires little to no time off from work, which is ideal for the fast-paced urban life nowadays. Clinical experience and experiments have proven that long-term skin rejuvenation is not only harmless to the skin, but can also significantly slow down the rate of skin aging and play the role of “eternal youth”. In addition to the common lasers mentioned above, many other types of cosmetic lasers have their own therapeutic characteristics, but all have the unique safety of pulsed lasers. These pulsed lasers have given dermatologists a new sense of confidence when it comes to finding the source of perfect skin for beauty lovers, leaving behind the “embarrassing” history of many skin problems that could only be diagnosed but not properly treated. In general, the results of pulsed laser are satisfactory as long as the patient follows strict post-operative instructions, such as sun protection. With the introduction of new technologies, many diseases that are currently difficult to cure will gradually achieve the desired results. For example, in the treatment of blood vessels, the latest Cynergy laser platform is gaining the attention of medical professionals worldwide. The concept of combination therapy is gaining attention, and the combination of two or more lasers or lasers with other techniques, such as injectable fillers, may lead to more satisfying results. Although “the best tool for the job” may not be the best tool for the job, a professional and experienced dermatologist is also the key to successful aesthetic results. Therefore, it is especially important to choose a professional medical unit before treatment.