We made a retrospective study of patients with Down's syndrome that were surgically treated for correction or palliation for their congenital heart disease between january 1996 to december of the 2000 in the National Institute of Cardiology "Ignacio Chávez". We analyzed these variables: age at the surgical moment, sex, congenital heart defect, pulmonary arterial pressure, type of surgery, time of stay in the intensive care unit, complications and mortality. In this period they were surgically treated 37 patients. The mean age was of 2 years with 8 months with a range of 2 months to 17 years. The interventricular defect was the most frequent one (35%) and it was associated to persistent ductus arteriosus in the 61% of the cases. Six patients (16%) had atrioventricular septal defect, the half of them type A and other half type C of Rastelli classification. Twelve patients (32%) had one lesion persistent ductus arteriosus. Three patients had tetralogy of Fallot and two atrial septal defect. Pulmonary hypertension was found in 90% of the patients, in 23 was severe (62%), moderate in 5 and slight in 6 (16%). The surgical treatment was corrective in 89% patients and the average time of stay in intensive care unit was of 2.5 days. The most frequent complication was rhythm and conduction disorders, in 8 patients (22%), three with complete AV block and the mortality was of 8%. In the patients with Down's syndrome is important a complete clinical evaluation with an eye toward establishing an opportune surgical treatment.