Arteriosclerotic occlusive disease (ASO) is a systemic disease that mainly involves the large and medium arteries throughout the body and causes manifestations of lower extremity ischemia when the abdominal aorta and its distal vessels are involved. It is prevalent in men, with an age of onset of 45 years or older, and is often associated with multiple sites of atherosclerotic disease. It is often associated with hypertension, hyperlipidemia, coronary artery disease and diabetes mellitus. A significant number of patients are often misdiagnosed as “vasculitis” because they have not been seen by a formal vascular surgeon. Clinical manifestations and Fontaine’s stage: Stage I: no symptoms, or only a slight numbness, cold sensation. The affected limb is pale, the skin temperature is low, and the dorsalis pedis artery and posterior tibial artery pulsation is weakened. Stage II: The main manifestation is intermittent claudication. The skin temperature of the affected limb is lower and paler, and may be accompanied by toenail deformation, muscle atrophy, and loss of pulsation of the dorsalis pedis artery and posterior tibial artery. Stage III: The main manifestation is resting pain. The pain is severe and more pronounced at night, and the patient often stays up all night holding the foot. It may be accompanied by swelling of the distal limb. At this time, the artery is extensively narrowed and occluded, and the tissue is on the verge of necrosis. Stage IV: The symptoms are more severe, and in addition to resting pain, there is blackening and drying of the finger (toe) end of the affected limb and gangrene of the limb. In case of secondary infection, it manifests as wet gangrene with fever and other toxic symptoms. Differential diagnosis: ASO needs to be differentiated from other diseases that cause lower limb ischemia, such as thrombo-occlusive vasculitis, polyarteritis, diabetic foot, etc. Treatment: 1. Non-surgical treatment, including smoking cessation, moderate exercise, reduction of high blood lipids, application of drugs to improve circulation and dilate blood vessels. 2, surgical treatment, the main surgical methods are as follows: (1) endovascular treatment, including balloon dilation and shaping, endovascular stent implantation. Mainly used for short segment stenosis and occlusion of iliac artery and femoral artery. (2) Endarterectomy (3) Arterial bypass surgery, using artificial vessels or autologous vein bypass. A patent arterial inflow and outflow tract is required. (4) Lumbar sympathectomy (5) Large omental graft (6) Venous arterialization (7) Stem cell transplantation (8) Amputation.