1, hypertension and atherosclerosis, is the most important and common cause of cerebrovascular disease. Some data show that 93% of patients with cerebral hemorrhage have a history of hypertension, 86% of patients with cerebral thrombosis also have a history of hypertension, and 70% of patients with cerebrovascular disease have a history of atherosclerosis. 2, heart disease, is one of the main causes of cerebral embolism. Rheumatic, hypertensive, coronary arteriosclerotic heart disease and subacute bacterial endocarditis may produce attached wall thrombus, and when heart failure or atrial fibrillation occurs, it prompts the thrombus to dislodge and flow to cerebral artery and embolism occurs. Since the embolus can be dislodged repeatedly, it is easy to recur. 3.Aneurysms and arteriovenous malformations caused by abnormal development of intracranial vessels are common causes of subarachnoid hemorrhage and cerebral hemorrhage, and they often rupture and bleed several times. 4.Some inflammatory diseases can invade meninges and cerebral vessels, or invade cerebral vessels alone to cause cerebral arteritis, such as septic, tuberculosis, mycobacterial inflammation and rheumatism, all of which can cause cerebrovascular disease. 5, blood diseases such as thrombocytopenic purpura, erythrocytosis, leukemia, often cause hemorrhagic cerebrovascular disease. Ischemic cerebrovascular disease occurs in a few cases. 6, metabolic diseases such as diabetes mellitus, hyperlipidemia, etc., are closely related to cerebrovascular disease. It is reported that 30% to 40% of patients with cerebrovascular disease have diabetes, and the incidence of atherosclerosis in diabetic patients is 5 times higher than normal people, the time of atherosclerosis occurs earlier than normal people, and the degree of atherosclerosis is also heavier. 7, all kinds of trauma, poisoning, brain tumor, brain tumor after radiation therapy, etc., can cause ischemic or hemorrhagic cerebrovascular disease.