The diagnosis of cholesteatoma is clinical symptoms. CT is the gold standard imaging technique. In case of suspicion of a recurrent cholesteatoma in an obliterated mastoid, diffusion weighted MR (DWI) has shown a better result. The treatment of cholesteatoma is surgery. Eradication surgery can be done with canal wall up mastoidectomy, canal wall down mastoidectomy, radical mastoidectomy and mastoid obliteration. Reconstructive surgery is performed next for hearing preservation. In case recurrent cholesteatoma, a second on look surgery is needed. The hearing result after cholesteatoma surgery depends on several factors including the type of surgery technique, the degree of ossicular damage and type of reconstruction.