Arachnoid cysts can be divided into two categories, congenital and secondary (traumatic and post-infectious), depending on their etiology. Congenital arachnoid cysts are pouch-like structures formed when cerebrospinal fluid is enclosed within the arachnoid membrane and does not communicate with the subarachnoid space. Secondary to arachnoid adhesions, cysts form in the subarachnoid space and contain cerebrospinal fluid. It is a common clinical condition. So, do arachnoid cysts require surgery? The popular views are as follows: (1) intracranial hemorrhage (subdural or intracapsular), increased intracranial pressure, recurrent seizures and obvious symptoms of focal neurological impairment due to cysts are feasible for surgical treatment; (2) asymptomatic intracranial arachnoid cysts have different views on treatment: (1) no surgery: most scholars believe that symptoms can disappear on their own without surgery, or even cysts disappear naturally; meanwhile, surgery (2) Surgery: A few scholars believe that intracranial arachnoid cysts have the potential of unpredictable enlargement and the risk of death by hemorrhage, so surgery is advocated; (3) Close observation and standby surgery: For asymptomatic or asymptomatic patients, dynamic monitoring of intracranial pressure is feasible for 48 to 72 hours. If the intracranial pressure is within the normal range, surgery is not possible for the time being. If the intracranial pressure rises with abnormal waveform or the cyst increases progressively, surgery is feasible.