Endocardial cushion defects is a rare congenital heart disease. We experienced two complete endocardial cushion defects[ECD] and three partial ones, which were successfully repaired between 1986 and 1987. In a patient of complete ECD, associated with secundum ASD, Pulmonary stenosis and Down`s syndrome, the atrial and ventricular septal defects were closed separately with bovine pericardium and Dacron patches respectively, and then pulmonary stenosis was relieved by transannular patch widening in addition to valvotomy and infundibulectomy. In another patient with complete ECD, small interventricular communication was closed with simple suture with pledget and primum ASD was closed with pericardial patch. In first patient of partial ECD, primum atrial septal defect was closed with pericardial patch. In second patient of partial ECD, associated with secundum ASD, direct closure of secundum ASD and patch closure of primum ASD were performed. In third patient of partial ECD, associated with patent foramen ovale[PFO], primum ASD was closed with bovine pericardial patch and PFO was closed directly. In all patient except third patient of partial ECD, mitral clefts were closed with three or four 5-0 prolene interrupted sutures. Transient A-V dissociation developed postoperatively in two patients and transient nodal rhythm developed postoperatively in other two patients. Heart failure in complete ECD with Down`s syndrome was overcome with medical treatment.