The bulging blood vessels on the legs are caused by varicose veins, most varicose veins are due to congenital weakness of the vein wall, formation of high pressure within the veins, bad venous valves, resulting in stasis of blood in the superficial veins, over time the blood vessels will form in the lower extremities, the blood vessels are obvious, even tortuous, dilated, in the form of clusters and earthworms, which is clinically known as varicose veins, this bulging blood vessels on the legs is a typical varicose veins. In addition, some risk factors such as the nature of standing and standing work, obesity, lack of exercise, pregnant women, long-term oral hormonal drugs, etc., are also risk factors for causing and aggravating varicose veins. Therefore, patients with related risk factors must control the risk factors, and once this symptom of bulging blood vessels on the legs appears, they also need to consult a professional doctor in the vascular surgery department of a regular hospital to choose the appropriate treatment according to their situation.