10 patients with mitral regurgitation associated with various congenital cardiac anomalies were treated by reconstructive techniques in the Department of Thoracic and Cardiovascular Surgery, Hanyang University Hospital during the period of 2 years from 1982 to 1984. There were mitral valvular cleft in one case, chordae tendineae rupture associated with congenital multiple cardiac-anomalies [VSD, PDA, prolapse of aortic non-coronary cusp through VSD] in one case, elongated chordae tendineae after removal of left atrial myxoma in one case, and mitral annular dilatation associated with VSD in 3 cases, large PDA in 2 cases, aortic regurgitation [bicuspid valve] in one case, and unknown origin in one case. Owing to the various pathology above mentioned, reconstructive surgical approach to mitral incompetence is accordingly complicated and a combination of the following different procedures were properly used case by case, that is, suture of chordae tendineae, shortening of elongated chordae tendineae, closure of VSD, ligation of PDA, aortic valvuloplasty, mitral annuloplasty with mattress suture, etc. All patients were survived and they have been excellent postoperative results.