Intracranial aneurysm is a cerebrovascular disease with subarachnoid hemorrhage as the main manifestation. Its incidence is much higher than people think. Among cerebrovascular diseases, intracranial aneurysm ranks third after cerebral thrombosis and hypertensive cerebral hemorrhage. Intracranial aneurysm is not a tumor, but a localized bulge in the wall of intracranial blood vessels, like an inflated rubber hose, which is equivalent to an “untimely bomb” in the skull and has a very high death or disability rate once it ruptures. Nearly half of the patients die upon first rupture. Even if the aneurysm survives, the risk of re-rupture is extremely high. If the aneurysm is not treated promptly, most patients will die within a few years, making it a veritable “cold-blooded killer. However, it is a curable disease and with the development of science and technology, most patients can recover after treatment. Clinically, ruptured aneurysm bleeding is often highlighted by a severe headache, which patients describe as painful like cracking or exploding. All intracranial hemorrhage is considered to be cerebral hemorrhage in the eyes of the general public. Cerebral hemorrhage is a common name for many different kinds of hemorrhage, and aneurysm hemorrhage should be subarachnoid hemorrhage to be exact, which means that the location of the hemorrhage is on the surface of the brain. The brain is covered by several layers of membranes, one of which is called the arachnoid membrane, which is filled with fluid (cerebrospinal fluid) between the arachnoid membrane and the soft membranes (another layer) on the surface of the brain, the main role of which is to protect from the impact of external forces on the brain tissue. The most important thing in the subarachnoid space is the cerebral blood vessels, which may form aneurysms (which can also be referred to as hemangiomas in common parlance) due to localized outgrowth and bulging vesicles caused by factors such as hypertension and atherosclerosis. Aneurysms are usually asymptomatic and unnoticeable until they rupture, but once they rupture, they can cause severe headaches, nausea and vomiting, and even coma (caused by high brain pressure). Aneurysm rupture and bleeding is so dangerous that one simple description is: 1/3 death, 1/3 disability and 1/3 recovery. This is because about 15% of patients die before they can reach the hospital. The main treatments for aneurysms are open surgery (opening the cranial cavity, finding the aneurysm and clamping it with a clip) and interventional treatment (embolization with a special spring ring through the endovascular route and insertion of a tube at the root of the thigh), which aims to isolate the small bubble from the blood flow in the vessel. Of course, the need for immediate management of incidentally detected aneurysms is currently debated in academic circles, but if the following conditions exist, i.e., the aneurysm has increased in size during follow-up or the aneurysm is irregularly shaped, and the aneurysm is located in the brain, the necessary medical intervention can significantly reduce the risk of aneurysm rupture. The ideal management is to isolate the aneurysm from the normal blood flow. The methods of management are surgical clamping and endovascular intervention, both of which have advantages and disadvantages, depending on the specific shape of the aneurysm and the patient’s condition. The outcome is mostly satisfactory if the aneurysm can be treated promptly and properly before or after rupture. Because brain aneurysm is after all a benign lesion in the brain.