Objective To explore and conclude the influence factors of long-term outcomes of mitral valve repair for moderate and severe mitral regurgitation due to myxomatous degeneration.Methods To review the in-patient data and followup outcomes of 261 patients after mitral valve repair for moderate and severe mitral regurgitation due to myxomatous degeneration from Jan 1993 to Jan 2008 in Changhai Hospital of Second Military Medical University.Results There were 7 perioperative deaths and 254 survivors who obtained satisfactory perioperative outcomes.During the follow-up,24 patients were lost and 230 patients were followed up from 36 months to 174 months (77.3 ±30.3) months and follow-up rate was 90.6％.Multivariate Cox regression shows age ≥ 60 years old,left ventricular ejection fraction ＜ 0.50,undergoing combined coronary artery bypass grafting were the independent risk factors for long-term death after operations and left ventricular ejection fraction ＜ 0.50,New York Heart Association functional classification Ⅲ-Ⅳ,anterior leaflet prolapse were the independent risk factors for long-term recurrent moderate or severe mitral regurgitation after operations and prosthetic ring or band annulopasty was a protective factor.Conclusion The age ≥60 years old,left ventricular ejection fraction ＜ 0.50,undergoing combined coronary artery bypass grafting,New York Heart Association functional classification Ⅲ - Ⅳ,anterior leaflet prolapse,and prosthetic ring or band annulopasty were closely related with long-term adverse events after operations.