Objective To explorethe long-term prognosis of the triangular resectionvalvuloplasty for posterior mitral valve prolapse and provide a reference for the clinical treatment.Methods We retrospectively analyzed the clinical data of 61 pa-tients with posterior mitral valve prolapse underwent the mitral valvuloplasty in our hospital from Match 2008 to December 2016.30 patients who underwent triangular resection for posterior mitral valve prolapse.31 patients who underwentstandard quadrangular resection.The cardiac functional parameters and condition of mitral regurgitation were compared among the period of preoperation,discharging and follow-up.Results The mean follow-up period was 42 ±34(3-106)months.left atrium and left ventricular diameter were decreased(P<0.05).Inresrarch group,there was 1 patient who have moderate regurgitation,ar-rhythmia is one.In control group,there was arrhythmia in 1 cases,moderate regurgitation in 2 cases and death in 1 cases.Rate of freedom from reregurgitation was(97 ±6)% in research group and was(97 ±4)% in control group.There was no SAM in two groups.There were no significant differences of survival or risk of reoperation.There was a statistic difference of NYHA classification of cardiac function in the phase of follow-up than that of discharging(P<0.05).Conclusion Triangular resec-tion of a prolapsed posterior mitral leaflet is a simplified,reliable, reproducible, and durable procedure,like quadrangular re-section of a prolapsed posterior leaflet.