BACKGROUND AND OBJECTIVES: The goals of chronic ear surgery are infection control, closure of the ear drum by grafting techniques, and hearing rehabilitation via ossicular chain reconstruction. Many biocompatible middle ear prosthesis have been developed and enthusiastically endorsed as a suitable material for ossicular chain reconstruction. Such enthusiasm, however, has been largerly derived from data accumulated in the short term, often less than a year's follow-up. We intended to evaluate the long-term hearing results of the minimum 3 years follow-up period after ossicular chain reconstruction using Polycel and IONOS biocompatible middle ear prosthesis. MATERIALS AND METHODS: Fifty-eight cases who underwent ossiculoplasty in Chonnam University Hospital from February 1993 to November 1996 were retrospectively analyzed in this study. A successful hearing gain was defined as a postoperative air-bone gap of 30dB or less. RESULTS: The closure of air-bone gap to 30dB or less occurred in 53.7% using PORP shape prosthesis, 17.6% using TORP shape prosthesis. 78.6% of Polycel and 31.8% of IONOS revealed a successful hearing range. Good middle ear mucosal status showed better results than middle ear mucosa with granulation or cholesteatoma (p<0.05). But, preoperative Valsalva maneuver, canal wall up or down procedure, and stage operation didn't influence the statistical results. CONCLUSION: Both Polycel and IONOS middle ear prosthesis are not the ultimate solution in ossiculoplasty and the longer term follw-up period is needed when ossiculoplasty using biocompatible middle ear prosthesis such as Polycel or IONOS is planned.