We conducted a retrospective study of pediatrics with ventricular septal defect (VSD) that were surgically treated for correction between August 2001 and September 2004 in Songklanagarind Hospital, noting age at time of surgery, sex, type of defect, pulmonary arterial pressure, duration of stay in the intensive care unit and hospital, complications, and mortality. There were 93 patients with mean age 7.7±4.2 years. Perimembraneous VSD was the most frequent in this study (57%) followed by subarterial VSD (40.9%) and muscular VSD (2.1%). Pulmonary hypertension (PHT) was found in 100% of the patients; it was severe in 7 patients (7.5%), moderate in 58 (62.4%) and mild in 28 (30.1%). The average duration of stay in the ICU and hospital were 1.7±1.7 and 6.9±3.7 days, respectively; both were significantly longer in the severe PHT group compared to the mild and moderate PHT groups ( P < 0.05 ). Postoperative complications presented in 8 patients (8.6%), with 4 (4.3%) in the severe PHT group, 3 in the moderate group, and 1 in the mild group. Complete AV block was found in one patient in the severe PHT group. The overall mortality was 3.2% (2 in severe PHT, 1 in moderate PHT). We concluded that VSD with severe PHT continues to be a major cause of postoperative morbidity and mortality, and have increased the duration of ICU and hospital stay in these patients.