The most serious type of cholesteatoma is the middle ear cholesteatoma, which can lead to hearing loss and even deafness. Cholesteatoma is a continuous accumulation of keratinized squamous epithelium lined with a capsule filled with keratin debris. Cholesteatoma of the middle ear is a cystic lesion of complex squamous epithelial origin that occurs in the mastoid region of the middle ear. As the keratinized epithelial tissue builds up, it can progressively expand to involve neighboring structures, leading to hearing loss, vestibular dysfunction, facial nerve paralysis, and a series of intracranial and extracranial complications. Middle ear cholesteatoma can be divided into two types: congenital and acquired, and acquired is more common, accounting for about 98%, mostly caused by chronic middle ear mastoiditis and marginal perforation of tympanic membrane flaccid part or tense part, which is one of the types of chronic otitis media. The main clinical manifestations are long-term pus flow in the outer ear, increased secretion, hearing loss, and even conductive deafness. Marginal perforation of the flaccid or tense part of the tympanic membrane, with red crumbly or bean dregs-like material inside the tympanic cavity visible at the perforation, with a special foul odor. If cholesteatoma is diagnosed, early standardized treatment is recommended to reduce the adverse effects of the disease.