The most effective test to determine the cause of subarachnoid hemorrhage is cerebral angiography, which examines the brain for vascular malformations and the presence of stenoses and aneurysms. The common causes of subarachnoid hemorrhage include cerebral aneurysms and arteriovenous malformations. Patients with acute onset of hemorrhage may have sudden onset of explosive headache in most patients, as well as nausea and vomiting. Other etiologies that cause subarachnoid hemorrhage include hypertension and cerebral atherosclerosis. If the patient is hospitalized promptly after the onset of the disease, comprehensive treatment should be carried out, and surgical treatment should be considered when surgery is appropriate, while conservative treatment is the main treatment if surgery is not suitable. Patients should be instructed to avoid emotional agitation and dry stools, as well as bed rest, cranial pressure-lowering therapy and neuroprotective therapy.