Objective To summarize the clinical experiences of the application of posterior leaflet chordal transfer in the treatment of anterior mitral leaflet prolapse, and to investigate the best time for mitral valve repair. Methods From October 2004 to October 2008, 16 patients with anterior mitral leaflet prolapse underwent mitral valve repair. The echocardiography diagnosis revealed that 10 patients had chordal rupture, 4 had chordal elongation, 2 had both rupture and elongation. And there were 3 with A1 segment prolapse, 6 with A2 segment prolapse, 3 with A3 segment prolapse, 2 with both A1 and A2 segment prolapse, 2 with both A2 and A3 segment prolapse. All the patients underwent posterior leaflet chordal transfer, and one of them with coronary artery disease underwent coronary artery bypass grafting. Results There was no operative death. The echocardiography examination revealed that there were 2 patients with mild regurgitation, 6 with trivial regurgitation and 8 with no regurgitation before discharge. The patients received nticoagulation treatment of warfarin for 3 months after discharge. All the patients were followed up for 1-46 months(22.0±3.5 months). The echocardiography examination showed that there were 3 patients with mild regurgitation, 7 with trivial regurgitation and 6 with no regurgitation. There were 12 patients with New York Heart Association(NYHA) classⅠ, and 4 with class Ⅱ. The left ventricular ejection fraction(LVEF) was lower than that before operation(53.0%±3.4％ vs.65.0%±4.2％,P=0.013),and there was no statistical significance compared with that before operation(61.0%±2.1％vs.65.0%±4.2％, P=0.110). The left ventricular end diastolic diameter decreased significantly compared with that before operation(50.0±3.2 mm, 47.0%±2.8 mm vs.580±6.5 mm，P=0.031，0020). The postoperative cardiac function improved significantly (P=0.002). Conclusion Posterior leaflet chordal transfer is an effective method for anterior mitral leaflet prolapse. The best time for mitral valve repair is when LVEF＞60%, left ventricle enlarges a little, and NYHA class＞Ⅲ before operation.