Unilateral tinnitus may be a precursor of cancer, but the chance of occurrence is low. The specific cause of tinnitus can only be diagnosed after professional examination at the Department of Otolaryngology. Tinnitus is a relatively common clinical symptom, and its causes are usually seen in acute and chronic otitis externa, cerumen embolism, acute and chronic otitis media, tympanic membrane perforation, sensorineural tinnitus, and auditory neuropathy. In addition, hypertension, arteriosclerosis, anemia, malnutrition, psychosomatic diseases such as anxiety, depression or neurosis can also lead to unilateral tinnitus symptoms. A few patients with external auditory canal cancer, middle ear mastoid cancer or nasopharyngeal cancer tumor compressing the eustachian tube have unilateral tinnitus as the first symptom, but such cases are rare. It is recommended to go to the ENT department of a regular hospital as soon as possible after the occurrence of unilateral tinnitus, so that relevant examinations can be conducted under the guidance of a doctor to clarify the cause and adopt a reasonable treatment plan.