Exercise capacity in compromised post-operative patients with right ventricular outlet tract lesion is known to be impaired. The aim of this study was to evaluate the different degree of exercise capacity in volume or pressure overloaded RV and to find associated parameters. Thirty-seven patients were enrolled in this study to evaluate exercise capacity by cardiopulmonary exercise test using programmable treadmill. They were divided into two groups who had significant pulmonary regurgitation (PR) without significant pulmonary stenosis (PS) after tetralogy of Fallot correction (21 patients, mean age: 14.3 ± 3.7 years) and significant PS after RV to pulmonary artery conduit interposition or REV operation (16 patients, mean age: 16.6 ± 3.7 years). We checked serum B-type natriuretic peptide level, QRS duration in electrocardiogram, and echocardiography to know LV and RV function. Patients with PR showed PR fraction of 39.6 ± 12.5% in MRI. Patients with PS showed pressure gradient of 57.9 ± 15.6 mmHg in cardiac catheterization. Progressive exercise time was significantly longer in the patients with PR than PS (10.5 ± 2.5 vs. 8.7 ± 2.3 minutes, p = 0.037). Peak oxygen consumption showed no significant difference between two groups (32.1 ± 6.3 in PR group vs. 29.8 ± 6.5 mL/kg/min in PS group, p = 0.617). Serum B-type natriuretic peptide level was higher in the patients with PS, but showed no significant difference (41.3 ± 17.1 vs. 33.3 ± 23.9 pg/mL, p = 0.123). QRS duration was higher in the patients with PR, but showed no significant difference (144.6 ± 22.1 vs. 133.8 ± 24.0 msec, p = 0.13). RV Tei index from tissue Doppler image in RV free wall increased with borderline significance in PS group than PR group (0.51 ± 0.11 vs. 0.45 ± 0.06, p = 0.08). Other echocardiographic parameters such as LV ejection fraction, Tei index, tissue Doppler image showed no significant difference between two groups. In conclusion, there was no significant difference of exercise capacity except progressive exercise time between clinically significant PR and PS group considering similar LV functional status.