Brain tumor, i.e. intracranial tumor, is a tumor of the nervous system that occurs in the cranial cavity. The pathogenesis is not yet clear, and most believe that it may be related to ionizing radiation. Brain tumor is a progressive disease. When the tumor is small in size, that is, there are no obvious clinical symptoms in the early stage, and there are no so-called 7 signs and symptoms. When the tumor grows to a certain extent, it will compress the surrounding nerves, blood vessels and brain tissues, and then more obvious clinical symptoms will appear, which can be summarized as the following aspects: 1. Sensory system: 1. The tumor of cerebellar hemisphere is mostly associated with hemilateral limb weakness and even hemiparesis, as well as impaired perception of pain and temperature, while the tumor of cerebellar hemisphere is mostly associated with ataxia of one limb, unstable walking and slow movement, etc.; 2. If the patient has no previous history of otitis media or trauma, but suddenly appears to have hearing loss on one side, sometimes accompanied by tinnitus, it is considered to be caused by tumor compression of the auditory nerve. Neurological system: 1. Morning headache: the pain is usually more obvious in the morning, and in severe cases, the pain may affect sleep; 2. Seizures: if seizures occur in adulthood and there is no other cause, brain tumor may be considered. The vomiting is different from vomiting in gastrointestinal disorders. It usually does not occur after eating and most of the seizures occur after a headache, and the headache may decrease after vomiting. Respiratory system: As the temporal lobe in the lower part of the brain is stimulated by the tumor, the patient can often smell odors that do not exist in reality. V. Endocrine system: Amenorrhea and lactation in women during non-pregnancy period are often considered as symptoms of intracranial pituitary tumor.