Most cerebral aneurysms are discovered only after rupture and bleeding or compression symptoms occur. However, some people may come to the clinic due to headache or dizziness, and a brain aneurysm is found accidentally after various tests; others have no symptoms normally, but a brain aneurysm is found during a health checkup. Should we operate immediately after finding a brain aneurysm? Are there any other options? Although there are some controversies about the timing of surgery for cerebral aneurysm, there is basically a consensus that, in general, once a ruptured cerebral aneurysm is diagnosed, it should be treated as an emergency; for a non-ruptured aneurysm, if there are symptoms of pressure such as cranial nerve palsy, surgery should be performed within a certain period of time; if there are no symptoms, surgery can be performed at a later date or under conservative observation. The question arises again, under what circumstances should we choose active surgery and under what circumstances should we choose conservative observation for asymptomatic aneurysms? Surgery has the risk of complications, while conservative observation has the risk of natural rupture, so how to weigh and choose has become a hot issue for both doctors and patients, and precisely on this issue, there is still some controversy in the medical community. A group of foreign follow-up studies on unruptured cerebral aneurysms showed that the annual rupture rate was 1.4%, the average time from aneurysm detection to rupture was 9.6 years, and the 30-year cumulative rupture rate was 32%. Another study, titled the International Study of Unruptured Intracranial Aneurysms (ISUIA), is the largest study of unruptured aneurysms conducted to date, including 1449 patients with unruptured aneurysms in the United States, Canada, and Europe, with a mean follow-up of 8.3 years and an annual rupture rate of 0.05% to 0.5%. What impression do these epidemiological data give us? That the natural course of asymptomatic aneurysms is not as aggressive as thought and the benefit/risk ratio of surgical treatment of asymptomatic aneurysms is not as high as expected. Therefore, some foreign scholars have suggested that conservative observation and regular follow-up may be a safer option for asymptomatic aneurysms found incidentally, especially those less than 1 cm in diameter. The significance of aggressive surgery was affirmed in another large case study of unruptured aneurysms in the U.S. This study included 14,050 patients with unruptured aneurysms treated by craniotomy or intervention and plotted the risk curves of both procedures with age; it also cited data from four internationally known studies on the natural regression of unruptured aneurysms and plotted the risk curves of natural rupture with age, finally concluding The conclusion of “no craniotomy at age seventy and no intervention at age eighty” means that for unruptured aneurysms, craniotomy is not recommended above age seventy (but intervention can still be considered), and intervention is not recommended above age eighty because the surgical risk is increased in patients of advanced age; conversely, for unruptured aneurysms younger than age seventy, active surgery is recommended; for patients older than age seventy, active surgery is recommended. patients, active surgical treatment is recommended; for patients older than seventy and younger than eighty, open treatment is not recommended anymore, but the benefit of interventional treatment is still obvious. Although controversial in the literature, there is a basic consensus in China on the indications for surgery for asymptomatic aneurysms. In general, asymptomatic aneurysms <5 mm in diameter with regular morphology can be monitored dynamically, and follow-up means include MRA and CTA, which are noninvasive tests. Aggressive surgery may be recommended in the following cases: (1) aneurysms ≥5 mm in diameter; (2) irregular morphology; (3) modest expected risk and difficulty of surgical treatment; (4) aneurysms <5 mm in diameter should be judged on the basis of their morphology, location, number and patient condition, etc. Aggressive intervention is recommended in patients with the following conditions: aneurysms with subcapsules, multiple, located in the anterior communicating artery, posterior communicating artery and post circulation, patient life expectancy >10 years, previous history of subarachnoid hemorrhage, family history, or the need for long-term oral anticoagulation and antiplatelet medications; (5) a tendency for the aneurysm to increase in size during follow-up observations. In conclusion, the asymptomatic aneurysm found by chance has a potential risk of distant bleeding and serious consequences in case of rupture, so whether to perform interventional treatment or not requires comprehensive clinical consideration, including adequate communication between doctors and patients.