Between January 1970 and March 1984, external conduit repair was performed in eighty-five consecutive patients for various complex anomalies. The age at operation ranged from 2 months to 47 years, and 41 patients were in an age group of 5 to 9 years. Among 85 complex anomalies, 20 cases of d-transposition with VSD + PS, 33 cases of Tetralogy of Fallot with pulmonary atresia, 11 cases of truncus arteriosus and 11 cases of 1-transposition were included. From January 1970 to December 1975, conduits used were aortic homograft in 1, formalin treated porcine valved conduits in 27, and valved conduits treated with 0.65% glutaraldehyde in 3 and from January 1976 to November 1982, 42 Hancock composite grafts were used. Since December 1982, valved conduits made of preserved pericardium treated with glutaraldehyde were employed. In sixty-one patients survived from operation, actuarial survival rate was calculated as 87% at five years, 82% at ten to fourteen years. However, systolic pressure of right ventricle after repair mostly affected actuarial survival rate which maintained 93% at twelve years in patients with systolic pressure lower than 80 mmHg, and reduced to 65% at fourteen years in patients with that higher than 80 mmHg. Although external conduit repair was valuable for surgical treatment in complex anomalies, proper selection of conduit material, prevention of infectious endocarditis, and pseudoendothelial proliferation in late stage were the problems to be solved in the future.