The purpose of this study was to analyze our results of mitral valve repair with a rigid annuloplasty ring (Carpentier-Edwards ring; Baxer-Edwards CVS Laboratories; Lrvine, Calif) in terms of its efficacy and safety. We have examined postoperative mitral regurgitation (MR) and left ventricular diastolic dimension (LVDd) in 63 cases of mitral valvoplasty during a period of 5 years. The operative methods were 20 cases of tendon reconstruction, 42 cases of quadrangular resection, and 15 cases of annuloplasty alone. Operative mortality and freedom from complications were examined at the mean 41.2 months after the operation. There were no operative deaths, and no case with severe MR postoperatively. From echocardiographic findings, the grade of MR changed from 3.13 to 0.28 postoperatively, and LVDd changed from 58.4±6.71 to 48.7±6.3ml postoperatively. Reoperation was performed in 2 cases (3.2%) several years after the first operation. The rate of midterm mortality was 4.8%. The postoperative mitral valve area was 2.85cm² in size of 26mm ring, 2.95cm² in size of 28mm, 3.09cm² in size of 30mm, which were measured from PHT (pressure half time) of the Doppler echocardiography. In conclusion, mitral valve repair with rigid annuloplasty ring (CE ring) provided good results for MR at midterm follow-up.