Sudden deafness, also known as idiopathic deafness or violent deafness, is a common emergency in otology, i.e., sudden onset of moderate to severe sensorineural deafness that can progress to severe deafness within minutes, hours or 1-2 days, often accompanied by tinnitus, and in some patients, vertigo, visual rotation, nausea and vomiting. The etiology of sudden deafness is unknown, and there are many possible causes and different pathogenesis, which may be related to inner ear microcirculation disorders, viral infections, metabolic disorders, autoimmune disorders, and sudden changes in inner ear pressure. The most distinctive feature of sudden deafness is the sudden onset of hearing loss and the perception of distant sounds. The incidence of sudden deafness is mostly in one ear, but about 4-17% in both ears, with approximately equal incidence in both ears and no significant gender differences. In recent years, the incidence of sudden deafness is increasing and the age is getting younger. Due to the development of society, the pace of life is accelerated, and social competition is fierce, which leads to mental tension, fatigue, and excessive pressure of life and work, etc., which can easily induce sudden deafness. If sudden deafness is not treated in time, it can cause lifelong deafness and should be taken seriously. About 1/3 of the patients may recover their hearing after sufficient rest, but most of the patients have to rely on medication, and the earlier the time of consultation, the better the effect. If treatment is started within a week of the onset of the disease, more than 80% of patients can be cured or recover some of their hearing. The likelihood of healing is significantly lower when treatment is not given for more than one month. Some patients are left with permanent and severe deafness. Therefore, once the symptoms of hearing loss, tinnitus, ear pain and stuffy ears appear, it is important to seek medical attention as soon as possible so as not to miss the opportunity of treatment. Early treatment with corticosteroids can significantly improve the efficacy.