We describe a male patient who presented a progressive conductive unilateral hearing loss 20 years after otosclerosis surgery. Computed tomography (CT) scan and magnetic resonance imaging (MRI) findings suggested a facial schwannoma in its tympanic segment. At the time of revision surgery, a facial schwannoma was found to originate at the tympanic segment, pushing the prosthesis out of the oval window fenestration. The Teflon-piston was repositioned with difficulties in the central platinotomy, and the facial schwannoma was left intact.