Meningitis is a cause of profound sensorineural hearing loss (SNHL) and can cause inner ear ossification, so called labyrinthitis ossificans (LO). Cochlear implantation is one of therapeutic choice in profound SNHL patient, but LO can be an obstacle of implantation. A 53-year-old man presented progressive both hearing loss for 2 years after meningitis. He had got a heart valve surgery previously. He had tried hearing aids, but acceptable gain was not obtained. On temporal bone CT and MRI, LO was seen on both ears. Right cochlear implantation was planned. After the opening of the round window, we inserted a sterilized dummy electrode array to ascertain the passage in the cochlea. There was a resistance while inserting the dummy array and further drilling was performed and the dummy electrode could be inserted. After then, the real electrode was inserted. All electrodes were successfully inserted, and successful audiologic result was seen at follow-up. In this report, using a dummy electrode array before the real one is one of the ways of confirming clear insertion of electrode array preventing possible damage of electrodes in cochlear implantation in patients with LO.