Meningiomas, which occur in about 15% of all cranial tumors, are the most common benign tumors in the adult skull. They are mostly slow-growing, often taking many years to develop, and rarely become malignant. It is because of their slow growth that meningiomas are sometimes detected only after the tumor has grown so large. Nowadays, many meningioma patients are diagnosed as an “accidental finding”, such as a CT scan after a car accident or other traumatic brain injury, and are diagnosed with a meningioma. Meningiomas that have developed clinical symptoms (e.g., epilepsy, weakness, sensory loss, cranial nerve dysfunction, etc.) should be treated surgically. For those small meningiomas without clinical symptoms (tumors less than 30 mm in diameter) observation can be preferred without surgery or gamma knife treatment. How to deal with specific cases should be decided by doctors with rich clinical experience. Suggested treatment: 1) patient’s age ≥65 years old; 2) tumor ≤30mm, among which for tumor size 20-30mm, we should consider whether to operate or not; 3) patient has no symptoms related to meningioma (to be judged by the doctor); 4) tumor is dense or calcified on CT scan; 5) no obvious cerebral edema around the tumor; 6) tumor enhancement is not very obvious; 7) meningeal tail sign is not typical; 8) tumor is located in non-important functional area. 8.Tumor is located in non-vital functional area; 9.Patient’s health condition is poor; 10.Patient has no fear of tumor and is willing to observe.