Background: The purpose of this study is to analyze mid-term results after correction of truncus arteriosus in one institution over 20 years. Methods: Between 1988 and 2007, 26 patients underwent total correction of truncus arteriosus and 1 patient underwent shunt operation. We conducted a retrospective chart review of their medical records. Results: 14 were male and 13 were female, median age at operation was 63 days (range 9days to 5.25 years) and median body weight at operation was 3.8kg (range 2.5 to 17). The median follow up period is 31.3 months. The early mortality was 11(40.7%). Out of 12 patients operated between 1988 and 1999, 7 (58.3%) were early mortality and 2 (16.7%) were late mortality. Out of 17 patients operated between 2000 and 2007, 3 (17.6%) were early mortality and 1 (5.9%) was late mortality. Their anatomic types were type I in 15 patients, type II in 9 patients, type III in 2 and type IV in 1 patient by the Collett-Edwards classification. 22 (81.5%) patients experienced Rastelli operation. At initial operation, we used 6 homograft, 5 porcine valved conduit, 5 home made valve and 6 valveless auto-pericardial roll for reconstruction of right ventricular outflow tract. There was no statistical significance between kinds of conduit and reopeation freedom period or survival rate. 11 patients (78.7% of survivor) experienced reoperation and the median time from initial operation to reoperation was 14.6 months. Reasons of reoperation were airway problem in 1 case, severe truncal valve regurgitation in 1 case and conduit failure or right ventricular outflow tract obstruction in 9 cases. During recent follow up period, 9 patients were NYHA functional class I and 3 patients were class II. Conclusions: Despite of the decrease of early mortality, mortality rate and reoperation rate are very high. However, survivors��� functional class is relatively good. Therefore truncus arteriosus remains a challenging entity of congenital heart disease.