Purpose: The aim of this study was to examine the effect of CPB temperature on clinical outcome in infants undergoing repair of isolated VSD. Methods: Of the 212 infants with isolate VSD and OHS between January 2001 and December 2010, 65 infants were enrolled. They were divided into two groups; group 1, hypothermia (26-29���) and group 2, near-normothermia (34-36���). Results: Thirty-four infants were group 1 and 31 patients were group 2. Age on OHS, gender, weight on OHS, and number of patients below 3-month-old showed no significant differences between group 1 and 2. In group 1, 5 infants were Down syndrome and 12 infants had admission for respiratory infection before OHS. In group 2, number of infants with Down syndrome and pre-OHS admission were 2 and 3, respectively. CPB time and ACC time in group 1 were longer than in group 2 (81 versus 58 minutes, p=0.000, 48 versus 37 minutes, p=0.004). One infant in group 1 had CPB weaning difficulty and one in group 1 was died due to infective endocarditis. Postoperative intubation duration and number of infants with postoperative residual shunt were 1.6 days and 2 in group 1, 1.8 days and 3 in group 2. There was no infant with postoperative neurologic and developmental abnormalities. Conclusion: This study revealed that in neonates and infants requiring correction of simple CHD, hypothermic and near-normothermic CPB could have similar clinical outcome. In addition, near-normothermic CPB could make shorter CPB and ACC time than hypothermic CPB. Considering the recent reports for relations between inflammation, perfusion temperature, and bypass time, near-normothermic CPB may be of benefit to neonates and infants requiring correction of simple CHD.