The facial nerve is the seventh pair of cranial nerves, its length of penetration is 3.1~3.3cm, and it is the most vulnerable nerve. The facial nerve originates from the cerebellar triangle of the cerebral bridge, exits the cerebral bridge, crosses the foot of the cerebellar bridge, and together with the auditory nerve, arrives at the inner ear gate, from which it enters the internal auditory canal, and enters the facial neural tube anteriorly and inferiorly at the base of the inner ear canal. The other portion passes outward between the vestibular cochlea to the geniculate ganglion. Inside the facial canal, it innervates the tympanic cord, the greater Iwata nerve, and the stirrup musculocutaneous nerve; The other part of the facial neural tube goes to the mastoid foramen of the stem and exits the cranium, then enters the isthmus of the parotid gland and divides into the upper and lower trunks before dividing into five branches, namely, the temporal branch, zygomatic branch, buccal branch, mandibular marginal branch and cervical branch. The facial nerve is a mixed nerve, including motor fibers that innervate facial muscle movement, taste fibers that innervate taste buds in the mucous membrane of the anterior 2/3 of the tongue, parasympathetic fibers that innervate secretion of the relevant glands, and general somatosensory fibers that innervate sensation of the skin of the ear or of the muscles of expression. Patients with facial nerve damage may have facial paralysis, loss of taste in the anterior 2/3 of the tongue, auditory hypersensitivity, decreased sensation in the external auditory canal of the auricle, etc. Once facial nerve damage is suspected, go to the hospital in time for treatment under the guidance of a doctor.