From July in 1997, cochlear implant has been performed for 11 postlingual deaf patients (6 male and 5 female, mean age, 53.6, mean duration of deafness, 6.1 years) in our clinic. The cause of deafness in two patients was streptomycin ototoxicity, sudden deafness in one, and unknown in the remaining eight. In all cases, the inverted U-shaped skin incision was used. The temporal bone was exposed, and a package bed for an implant device was made. Posterior tympanotomy was performed, and an electrode was inserted into the scala tympani. In one patient, at 2 days post-operation, epidural hematoma happened and the removal of the hematoma was required. The other 10 patients had no complication involving flap necrosis, electrode slip-out, facial nerve palsy, and device failure. All patients showed good restoration of speech comprehension.