Thrombo-occlusive vasculitis is a chronic occlusive disease of the blood vessels that manifests as segmental inflammation of the blood vessels and mainly affects the extremities, especially the small and medium-sized arteries and veins of the lower extremities. In 1908, Buerger reported the pathological changes of this disease, so it is also called Buerger’s disease. The disease occurs in young and middle-aged men. The exact cause of the disease is not known, but may be related to smoking, cold, chronic injury and infection, and autoimmune dysfunction. Patients usually do not have hypertension, hyperlipidemia and diabetes, which predispose to atherosclerosis. The lumen of the blood vessel is blocked by thrombus during the active phase of the disease, and the thrombus becomes fibrotic in the later phase. The nerves, muscles and bones in the blood supply area appear ischemic changes after the artery is blocked. The disease progresses slowly, and the main clinical manifestations are coldness, low skin temperature, pallor or cyanosis of the diseased limb; pain and abnormal sensation of the diseased limb, impaired mobility, intermittent claudication or resting pain. In the late stage, skin darkening, ischemic ulceration, and distal limb necrosis appear. The distal arterial pulsation of the diseased limb is weakened or absent. Wandering superficial phlebitis of the body surface is often present, sometimes mild and sometimes severe, and can improve on its own; angiography of the lower extremities may show thinning, narrowing, or even occlusion of the vessels below the calf. Thrombo-occlusive vasculitis occurs in young adults who are smokers. If the above symptoms occur, the disease should be treated at an early stage in a regular hospital, and ultrasound and arteriography can help to confirm the diagnosis.