Eosinophilic otitis media is an intractable middle ear disease with gelatinous mucoid fluid containing eosinophils associated with bronchial asthma and nasal allergy that sometimes induces deterioration of sensorineural hearing loss. Here, we report a case of eosinophilic otitis media in a 50-year-old woman who received a Nucleus 22 multi-channel cochlear implant in the right ear at the age of 42 years. She had received treatment for bronchial asthma, chronic sinusitis with nasal allergy and otitis media with effusion since the age of 30 years and had noted bilateral sudden deafness and vertigo at the age of 35 years. Preoperative CT and MRI showed cochlear ossification in the left ear, in which mastoidectomy was performed as treatment of eosinophilic otitis media. Long-term follow-up revealed that cochlear implant is indicated for deafness induced by eosinophilic otitis media, and an early decision for cochlear implant surgery is necessary. Steroid administration was remarkably useful in controlling eosinophilic otitis media in patients with bronchial asthma and chronic sinusitis with nasal allergy.