The prevalence of venous disease of lower limbs in China is 8.89%, with nearly 100 million patients. Varicose veins are a common disease of lower extremity veins, which can easily lead to various complications such as phlebitis, venous thrombosis and local pigmentation, skin ulcers, etc., seriously affecting patients’ aesthetics and quality of life. In the 19th century, saphenous vein ligation and stripping were the main methods of treating varicose veins in the lower extremities. in the late 20th century, “minimally invasive surgery” represented by lumpectomy developed rapidly, and radiofrequency ablation and laser closure also promoted the change of varicose vein treatment methods, and foam sclerotherapy was also developed in the same period. Sclerotherapy was once on the verge of being abandoned because of its incomplete treatment and high recurrence rate, but the introduction and application of foam sclerotherapy has made sclerotherapy re-recognized by people and has become one of the most important advances in the field of varicose veins in the past 10 years with its efficient, fast, safe and affordable features. The principle of sclerotherapy is not to directly clot and block the blood vessels, but to quickly strip the endothelial cells at the site of action after entering the varicose veins, causing vascular fibrosis and permanent occlusion of the blood vessels into fibrous strips, which are eventually absorbed by the body (Figure below). Spider varicose veins (i.e. capillary dilatation, which are veins less than 1mm in diameter) and reticular varicose veins (veins 1-3mm in diameter) are most suitable for sclerotherapy (as shown on the right) and can be injected on an outpatient basis, and the dilated veins can be seen to disappear once the injection is completed, and multiple injections can be staged for larger areas. Below is a comparison of the patient before and after treatment. For patients with heavy varicose veins, sclerotherapy can also be combined with interventional and surgical treatment to achieve minimally invasive and aesthetic results, requiring only a small incision below the groin, which is especially suitable for beauty lovers. With the widespread use in varicose vein treatment, the new sclerotherapy is gradually becoming known, and because it is safe, minimally invasive and aesthetic, it is bound to become more and more the first choice for varicose vein patients.