Gamma knife full name stereotactic gamma ray radiation therapy system, is a treatment of craniocerebral diseases based on large-scale therapeutic equipment, accept the gamma knife after the length of life depends on the disease and the patient’s personal situation, no conclusive. Gamma knife according to the principle of three-dimensional geometric orientation to the target tissues in the skull as the target, the use of gamma rays for a one-time large dose of focused irradiation, so that it produces focal necrosis or functional changes, with no craniotomy, the characteristics of small damage. Clinically, it can be used to treat primary brain tumor, brain metastases, epilepsy, cerebral hemorrhage caused by intracranial cavernous vascular malformations, etc. Depending on the primary disease being treated, the life expectancy of patients after Gamma Knife treatment varies. In the case of epilepsy or brain hemorrhage, Gamma Knife treatment generally does not affect life expectancy. In the case of primary brain tumors, life expectancy ranges from 1 to 10 years after surgery, depending on the type, size, location, and pathological grade of the tumor. In case of brain metastases, it depends on the treatment of the primary lesion and is difficult to be definitive. Patient care and follow-up treatment after Gamma Knife treatment is subject to the advice of a specialist.