Glioma is a malignant tumor, usually diffuse and infiltrative growth, most of them are large and diffuse, except for a few grade 1 or grade 2 gliomas that are small and located in non-functional areas can be cut, most of them cannot be cut at the cellular level. I often give patients an analogy that glioma is like the roots of a big tree, what we can cut off is only the main roots of the tree, but it is very difficult to remove all the small roots that are rooted in the distant soil, because there are many important functional areas in our brain tissue, such as motor and language, which will bring great dysfunction and seriously affect the quality of life in the future. Therefore, it is not possible to do unlimited resection. It is difficult to remove a glioma cleanly, so that not even a single tumor cell is left, so the remaining tumor cells need to be suppressed or destroyed by radiotherapy and chemotherapy to prolong the patient’s survival. Grade I gliomas are usually excised cleanly without radiotherapy, while those that are not excised completely require radiotherapy or chemotherapy. Most grade II and above require radiotherapy or chemotherapy depending on the specific case. The few grade II gliomas that have undergone extended resection may be selected for observation based on risk factor analysis. Grade III and IV gliomas basically require radiotherapy and chemotherapy.