The first is color Doppler ultrasonography, which is non-invasive and easy to perform, and can clearly understand the morphology of the aorta as well as the blood flow, and can detect whether there is an aneurysm or not. Next is CT examination, an enhanced CT can clearly diagnose whether there is an aneurysm or not, and CT angiography (CTA) is the most accurate and reliable method to diagnose abdominal aortic aneurysm, and can understand the shape, size and location of the aneurysm. In addition to CT, MRI can also confirm the diagnosis. Arteriography can also be done, but it is not a routine test because it is damaging to the body, and it is usually used when endovascular treatment is performed. One additional point is that most patients with aneurysms have atherosclerosis, which is a systemic disease that affects the blood vessels of the heart, brain, kidneys, lungs, and other organs. Therefore, aneurysm patients may have other diseases such as coronary heart disease, cerebral vascular sclerosis, and cerebral infarction at the same time. In the examination of aneurysm and preoperative preparation, it is necessary to pay attention to the corresponding examination and evaluation of important organs in other parts of the body, such as heart condition, electrocardiogram, echocardiogram, to understand the function of the heart and whether there is any myocardial ischemia in the heart, and brain, to understand the degree of cerebral arteriosclerosis, etc. These are for the further treatment of aneurysm. All these are to lay a safe foundation for further treatment of aneurysm.