Varicose veins of the lower extremities are a common clinical condition with a high incidence. Current international treatment of varicose veins in the lower extremities is manifested in three main areas: foam sclerotherapy, surgical spot stripping techniques, and endovenous radiofrequency or laser treatment. This is mainly due to the increasing cosmetic requirements and the aging of the population. Foam sclerotherapy is highly regarded and respected by medical experts both at home and abroad due to its easy operation, safety and reliability, mild patient pain and minimal trauma, and has been well received by patients. Sclerotherapy is the injection of chemical drugs into the lumen of blood vessels, perivascular, cystic cavity and body cavity, which produces the destruction of the intima, cystic lining and plasma membrane and mutual adhesion due to chemical inflammation, thereby occluding the lumen and producing tissue fibrosis to achieve the purpose of treating the disease. Foam sclerotherapy is developed on the basis of traditional sclerotherapy, which overcomes the shortcomings of traditional sclerotherapy, minimizes complications and recurrence rates, and broadens the indications, making it as effective as traditional surgery in treating varicose veins in the lower extremities. The Second European Conference on Coordination of Foam Sclerotherapy was held in Germany in 2006, which concluded that the promotion of the application of foam sclerotherapy has led to a revival of sclerotherapy as a minimally invasive treatment for varicose veins. In the last three years, the literature on the clinical application of foam sclerotherapy for the treatment of varicose veins in the lower extremities has increasingly appeared in the mainstream journals of vascular surgery, and the prospects for its application are appreciated by all.