In the past 20 years, mitral valve reconstructive repair has made great progress, and at present, about half of the mitral valve closure insufficiency cases can be improved by reconstructive repair of autogenous valves to improve valve opening and closing functions, thus avoiding valve replacement with a high incidence of postoperative complications. The method of mitral valvuloplasty depends on the specifics of the valve lesion, and in some cases simultaneous prosthetic annuloplasty is required. Advances in cross-sectional echocardiography are helpful in preoperative case selection. Mitral insufficiency without significant calcification of the valve and subvalvular tissues and good leaflet mobility can be considered for reconstructive repair. Mitral valve insufficiency can be caused by an enlarged annulus, excessive leaflet mobility, a leaflet free edge that is positioned above the orifice closure line during left ventricular contraction, and restricted leaflet mobility that interferes with opening and closing. These conditions may also coexist in the same case. After incision of the left atrium to expose the mitral valve, it is carefully determined whether the annulus is enlarged, whether the tendon and/or papillary muscles are broken or too long resulting in excessive leaflet mobility, and whether leaflet mobility is limited by junctional fusion, leaflet thickening, and tendon fusion, and then corrective surgery is performed according to the different lesions. Correction of annular enlargement is mainly by annuloplasty or annuloplasty with a prosthetic annulus, sometimes in conjunction with other orthopedic procedures. Posterior leaflet hypermobility, such as leaflet prolapse into the left atrium, is often caused by tendon rupture or excessive tendon length, and can be treated by removing the leaflets and annulus in a rectangular shape, suturing the annulus and leaflet margins, and performing annuloplasty with a prosthetic annuloplasty. In the case of prolapse of the anterior leaflet due to excessive activity, if it is caused by tendon rupture, the free edge of the prolapsed portion of the anterior leaflet can be fixed with 2 to 3 sutures to the adjacent thicker secondary tendon cords, or the thicker tendon cords of the posterior leaflet corresponding to the prolapsed portion of the anterior leaflet can be used to correct the anterior leaflet prolapse, and the triangular-shaped posterior leaflet at the site of the tendon cords is excised, and the incisional margins of the posterior leaflet are closed with sutures, and the separated posterior leaflet tendon cords and anterior leaflet tendon cords are removed and replaced with the posterior leaflet tendons. The separated posterior leaflet tendon cords and the prolapsed portion of the anterior leaflet were fixed with mattress sutures. In the case of prolapse of the anterior leaflet due to excessive length of the tendon cord, the excess length of the tendon cord can be embedded and sutured into a short incision on the top of the papillary muscle. In mitral valve insufficiency due to restricted leaflet mobility, the fused leaflet junction can be incised and the thickened secondary tendon cords pulling on the leaflets can be excised or the thickened primary tendon cords at the edge of the junction can be windowed, and the resection of the triangular fibrous tissue from the thickened tendon cords can free the leaflets and relieve subvalvular stenosis. In the case of an enlarged annulus, simultaneous prosthetic annuloplasty is required.