We all know that glioma is now treated by a trilogy of surgery, radiotherapy and chemotherapy. So why do you need surgery when you have glioma? There are two main purposes of surgery: The first is to clarify the pathological nature. Only when we get the tumor tissue can we do pathology to clarify the diagnosis. Nowadays, glioma pathology is composed of two parts: histopathology and molecular pathology. Histopathology can clarify whether the lesion is a glioma, its grade, and the level of malignancy. Molecular pathology can clarify which subtype the tumor belongs to, whether it is an astrocytoma or oligodendroglioma or other types. It can also help us to assess the prognosis, analyze the sensitivity of radiotherapy and guide the formulation of radiotherapy and targeted therapy, etc. For some tumors that are deeper in location, removal of the tumor will bring great risk and adverse consequences, or the tumor is so extensive that removal of a small part of the tumor will not solve the fundamental problem, then as long as the patient’s condition allows, we also try to recommend the patient to undergo a puncture biopsy or open biopsy to get the tumor tissue and clarify the pathological nature before proceeding to the next step of targeted treatment. Only when the pathological nature is clarified can the next step of treatment be carried out. Without knowing the pathological nature of the lesion, if the lesion is inflammatory or other benign lesions, blindly formulating radiotherapy and chemotherapy, sometimes will bring incalculable adverse consequences to the patient. The second objective is to remove the tumor. Glioma and its surrounding edema are compressive to the nervous system, leading to cranial hypertension and or neurological dysfunction, and severe cranial hypertension can be life-threatening. Tumor removal can solve the compression of brain tissue by tumor and edema, reduce intracranial pressure, improve the patient’s neurological symptoms and neurological function, and even save the patient’s life. In terms of postoperative treatment, in general, the current treatment options include: radiotherapy, chemotherapy, targeted therapy, immunotherapy and so on, all of which may have some effect on glioma, but most of them cannot achieve a cure. With the exception of oligodendroglioma, which has a better sensitivity to chemotherapy and radiation, all other types of gliomas have a limited sensitivity to chemotherapy and radiation, some slightly better and some worse. The dose of radiotherapy and chemotherapy that the human body can tolerate is limited, so within the limited dose of radiotherapy, the more tumors are removed and the fewer tumor cells are left, the smaller the load left for radiotherapy and chemotherapy, and the better the effect of radiotherapy and chemotherapy will be. That is why, our surgical principle is to remove the tumor to the maximum extent within the safe range, while preserving the patient’s important neurological functions, and the more tumors are removed the longer the survival may be.