Abstract: Objective:To evaluate the clinical effects of foam sclerotherapy in the treatment of great saphenous vein varicosis． Methods:Thirty cases(sides) with varicose veins in lower extremities were treated with high ligation of great saphenous vein and 1% polidocanol foam hardeners injecting into varicose vein of shank． The symptoms of great saphenous vein varicosis were observed． Results:All cases were successfully treated． The 20 ml of foam hardeners was used in each limb，no severe complications was found． The local lumps of varicose veins in 5 cases were found，no blood flow sign were detected by ultrasound，and the inflammatory response around varicose veins in 3 cases were found． The stem occlusion in 24 affected sides were confirmed by vascular ultrasound re-detecting in 2 weeks and 3 months after treatment． The average follow-up period was 3 months，the clinical symptoms in 24 cases were significant alleviated，varicose veins in lower extremities were disappeared，and the ulcer in two sides were cured in two months after operation． Conclusions:The effects of foam sclerotherapy in the treatment of great saphenous vein varicosis is good． The treatment combined with high ligation of great saphenous vein can increase the safety，which is a new means for treating great saphenous vein varicosis．