Cerebral vasospasm is common in aneurysmal subarachnoid hemorrhage (aSAH). It often occurs several days after aSAH, and then peaks at 1 week, causing local cerebral ischemia, cerebral infarction and neurological deficit dysfunction. Cerebral vasospasm is an important reason for death or disability after aneurysm rupture. Cerebral angiography is the gold standard for the diagnosis of cerebral vasospasm, but now transcranial Doppler ultrasound, CT cerebral perfusion imaging, near infrared spectroscopy and other non-invasive inspection methods are increasingly popular and easy to carry out extensively. Treatments of cerebral vasospasm include hemodynamics and drug therapy, with early removal of hematoma, diastolic blood vessels, and enhanced brain perfusion as the main research direction. Joint treatments are the future trends of cerebral vasospasm therapy. In this review, we summarized the diagnosis and treatment of cerebral vasospasm after aneurysmal subarachnoid hemorrhage.