Objective:To analyze the clinical characteristics of necrotizing otitis externa(NOE) and to discuss its clinical staging and treatment.Methods:A retrospective case series study was conducted in the Otorhinolaryngology Head and Neck Surgery Center of Beijing Friendship Hospital. Patients hospitalized in our department with diagnosis of NOE between June 2015 to December 2021 were included. There were 23 patients (23 affected ears), with 19 males and 4 females, aged 32-85 years (the median age was 68 years old). We analyzed and summarized the main symptoms and signs, laboratory examinations, imaging examinations, treatments and prognosis of the patients, and established a database for data collection and sorting.Results:All the 23 patients had various complications. There were 19 cases of type 2 diabetes, 5 cases of anemia, 3 cases of hypoalbuminemia, 2 cases of chronic renal insufficiency, and 1 case of uremia. The main symptoms on admission were otalgia, otorrhea, hearing loss, angular deviation, limited mouth opening, dysphagia and hoarseness. Physical examination showed swelling of the external ear canal (EEC), granulation tissue of the EEC, thin purulent secretion of the EEC, facial paralysis, restricted mouth opening, and decreased vocal cord movement. Etiological results showed 15 cases of Pseudomonas aeruginosa, 5 cases of Staphylococci and 3 cases of Aspergillus fumigatus. Imaging mainly showed abnormal soft tissue shadows of the EEC and middle ear, and temporomandibular joint, parapharyngeal space, skull base, intracranial and other adjacent structures were involved according to the different invasion directions of the lesions. According to the characteristics of these patients, we summarized a diagnostic criteria and clinical staging. All patients received systematic anti-infection, surgery and symptomatic support treatment. Until January 30, 2022, 4 patients died, including 1 case of extensive intracranial infection caused by NOE, and 3 cases of other systemic diseases after the affected ears were recovered and discharged from hospital. The other 19 patients′ ears were cured, the symptoms of otalgia and otorrhea disappeared, and the epithelization of the surgical cavity was good. Conclusion:The clinical manifestations of NOE lack specificity, and the diagnosis should be made according to the medical history, physical examination and auxiliary examination. According to different clinical stages, corresponding treatment measures should be formulated. The treatment is based on multidisciplinary comprehensive treatment, mainly surgical treatment. Early intervention has a good prognosis, otherwise, multiple-group of cranial nerve injury or intracranial infection implies poor prognosis.