Brainstem evoked potential examination is a more sensitive objective indicator of brainstem damage, which can objectively and sensitively reflect the function of the central nervous system, mainly to check whether the nerves in the brainstem area, i.e., the bite-auditory nerve pathway is open, and can also be used to check the brainstem response in some comatose patients. For brain dead patients, brainstem evoked potential examination can be used to determine if brain death exists. Usually, if a patient has hearing loss or lesions in the brainstem area, a brainstem evoked potential examination is needed to determine whether the findings are caused by damage to the auditory nerve or lesions in the auditory nucleus. Brainstem evoked potential examination is also commonly used for the differential diagnosis of patients with deafness, such as neurological deafness and sensorineural deafness. In addition, patients with optic neuromyelitis optica and multiple sclerosis can also undergo brainstem evoked potential examination to determine whether there is nerve damage in the brainstem area. Brainstem evoked potential examination has no age limit or pain, is simple, has high specificity, and is not affected by sleep, consciousness, sedative drugs, etc. It is an important reference value for the differential diagnosis of deafness and brainstem vascular diseases.