The treatment of otosclerosis is eminently surgical. Good immediate results have been well documented when stapedotomy or stapedectomy are chosen. OBJECTIVE This study aims to assess long term audiometric performance after otosclerosis surgery. METHODS this retrospective study enrolled stapedotomy and partial stapedectomy patients seen at our service with proven hearing improvement after surgery. Forty-one patients (47 ears) accepted the invitation to be reassessed. Audiometry results before and immediately after surgery were compared. RESULTS the median late follow-up was 11 years. To this date, 49% of the patients had normal hearing or mild dysacusis. Preoperative, postoperative, and late postoperative bone and air pure tone averages were 64.4 and 27.0 dB, 35.6 and 22.3 dB, and 44.1 and 29.5 dB respectively. CONCLUSIONS Otosclerosis surgery offers good long term results. Despite the worsening of thresholds, the level of hypacusis ten years after surgery is lower than the levels observed before surgery.