Introduction and OBJECTIVE: Cholesteatoma is the accumulation of exfoliated keratin within the middle ear or any pneumatized area of the temporal bone, with expansive capacity and bone lysis, leading to invasion of adjacent structures. The involvement of the inner ear is rare and is usually accompanied by hearing loss and facial paralysis. The aim of this study is to report a case with a large cholesteatoma and invasion of the inner ear. Case Presentation: An 84-year-old white man presented at the otorhinolaryngology service with constant otorrhea in his left ear for 2 years. Audiometry revealed bilateral hearing loss to deafness in his left ear caused by otorrhea. During otologic examination, abundant purulent discharge with tympanic membrane perforation in the left ear was observed. The mastoid tomography image showed hypodensity with soft tissue density filling the middle ear, destroying the ossicular chain and spur Chaussé, as well as all the mastoid trabeculae. In the inner ear, it was possible to see the damaged walls of the semicircular canals and the cochlea, extending to the proximal portion of the internal auditory canal. No surgical procedure has been performed because the patient's poor general condition. CONCLUSION: Despite being benign, cholesteatoma when not diagnosed early, can evolve with invasion and bone destruction and lead to complications such as facial paralysis and sensorineural hearing loss.