Tumors involving the brainstem involve the brainstem, cranial nerves, vertebral artery and basilar artery, ventricular pathway, and important structures or functional areas of the brain such as saddle area, pineal area, rocky-slope area, foramen magnum area, pontocerebellar angle area, jugular foramen area, etc. They are related to the patient’s life, neurological, endocrine regulation and conduction and other important neurological functions. Surgical damage to any of these areas may cause significant neurological dysfunction. In addition, most of these lesions are deep in the brain or skull base, so it is difficult to reveal them surgically. Therefore, it is difficult to remove the tumor and avoid damaging the brain stem, cranial nerves, important blood vessels and other important brain structures. The anterior superior brainstem mainly involves the third ventricle, hypothalamus, pituitary gland, fundic artery ring and other important tissue structures. The common tumor types include pituitary tumor, craniopharyngioma, meningioma, glioma, etc. This part of tumor usually pushes the midbrain from front to back when the tumor is large, and the brainstem symptoms are not obvious, and the tumor is easily separated from the brainstem. These tumors are usually easy to compress the middle cerebral aqueduct and cause symptoms such as hydrocephalus and difficulty in upward vision. The anterior part of brainstem mainly involves tissues and structures such as rock bone and slope, basilar artery and cranial nerve, etc. The common types of tumors include meningioma, chordoma, cholesteatoma and nerve sheath tumor, etc. The preoperative symptoms are milder and the course of disease is longer, but the tumors are deeper and more difficult to operate. The lateral side of brainstem mainly involves the pontocerebellar horn region, jugular foramen region and other tissues, and the common tumor types include neuroservix tumor, meningioma, cholesteatoma, glioma and so on. The posterior part of the brainstem mainly involves the fourth ventricle, cerebellar earth, cerebellar peduncle, etc. Common tumor types include medulloblastoma, ventricular meningioma, astrocytoma, glioma and vascular reticulocytoma, etc. These tumors usually cause hydrocephalus and cranial hypertension, and the tumor may invade the brainstem. These tumors may cause respiratory distress, hydrocephalus and cranial hypertension, and require delicate surgery because they affect the medulla oblongata. (7) Brain stem tumors, common types include astrocytomas and other gliomas and vascular reticulocytomas, with different clinical manifestations and treatment methods. Selecting and designing a good surgical approach is the key step to successful surgery. The general principle of designing the surgical approach is to facilitate the exposure and resection of the lesion while avoiding and protecting the important structures of the brain to the greatest extent possible. We usually select and design our surgical approach based on the classical approaches in the past, combined with the neurological navigation and the specific characteristics of the lesion. For example, for tumors near the saddle area, we use the inferior frontal approach, pterygoid approach or some modifications as appropriate; for tumors in the oblique area, we usually use the anterior sigmoid sinus or the combined supra-mural and sub-mural approaches. We have also successfully resected medulloblastoma with extensive involvement of the fourth ventricle, cerebellar earth, brainstem and one cerebellar peduncle using the inferior median occipital approach, while the posterior sigmoid sinus approach is mostly used for tumors in the pontocerebellar horn and pontineal area. The tumors in the pineal region can be used as appropriate. During surgery, attention should be paid to: ① For tumors closely related to the brainstem such as brainstem itself or glioma invading the brainstem, excessive removal of the tumor may damage the brainstem and cause respiratory disorders. Especially for those involving medulla oblongata or malignant tumors, total resection or near-total resection of tumors should not be pursued. For meningioma, nerve sheath tumor and cholesteatoma in the oblique region of rock, cerebellar pontocerebellar angle area (CPA area) and occipital foramen area, they can be separated from brainstem and basilar artery in general, so attention should be paid to differentiate and protect the surrounding cranial nerves. However, for tumors with tight adhesion to brainstem and important blood vessels, brainstem soft meninges with edema and large and hard tumors, total resection is very difficult and may cause serious complications, so do not force total resection. For gliomas that widely involve the fourth ventricle, cerebellar earth, brainstem and cerebellar peduncle, total resection or near-total resection of the tumor is also possible through a simple inferior median occipital approach. At the same time, postoperative mutism may occur due to the extensive damage to the deep nuclei of the cerebellar hemispheres and cerebellar peduncles in this type of surgery. ④When resecting the tumor, the base of the tumor or the main blood supply side is usually treated first. When dealing with the vessels, attention should be paid to protect the main stem and the small branches supplying the brainstem, and the tumor-supplying vessels should be coagulated close to the tumor. ⑤ When resecting the tumor, intracapsular resection can be performed first to leave space for separating the tumor edge. When separating the tumor, attention should be paid to using the discovered normal tissue interface to guide the separation, and at the same time, attention should be paid to using multiple angles and directions for separation in order to fully remove the tumor and maximize the protection of the adjacent important brain structures. (6) Due to the improvement of microscopic techniques, the tumor resection rate is getting higher and higher. For patients with preoperative ventricular access obstruction and hydrocephalus, the shunt or ventricular drainage used in the past is now used less and less. For these patients, if we think the tumor has been completely resected or nearly completely resected, and the ventricular access obstruction has been lifted sufficiently, we usually do not perform shunt or ventricular drainage, but perform dural repair and suture, and no hydrocephalus has been aggravated after the operation and need to perform hydrocephalus shunt again.