It is impossible to determine how long a patient can live in general with advanced malignant brain cancer, which is mainly related to the patient’s subsequent treatment, tumor type, metastases, as well as age and basic health condition. Generally speaking, both primary brain cancer in advanced stage and metastatic brain cancer in advanced stage have a poor prognosis, and most of them have a survival time of about six months to one year. If the patient’s basic health condition is good, and the metastases are fewer and smaller, and more sensitive to treatment measures, the patient’s life expectancy can be extended, but the exact length of extension cannot be determined and varies from person to person. If the patient is older, has poorer underlying health status, or has more or larger metastases, the prognosis is relatively poor and the survival period will be greatly shortened. However, active treatment can still effectively reduce patients’ pain and even prolong survival. In conclusion, how long a patient with advanced malignant brain cancer can live cannot be generalized and varies from person to person. It is recommended that such patients must adjust their mindset and take active treatment in order to improve the quality of life and prolong the life span.