Right ventricular (RV) function is an important determinant of clinical outcomes in children with hypoplastic left heart syndrome (HLHS). The modified Norwood procedure with a right ventricle to pulmonary artery conduit (RV-PA) has been widely performed for the initial palliation for HLHS, compared to the classic Norwood procedure with a modified Blalock-Taussig shunt. Recently bilateral pulmonary artery banding (bPAB) has been adopted in some centers in Japan for the first-stage palliation. It is argued that the bPAB will result in a more favorable hemodynamic profile and clinical outcomes. We investigate the hemodynamics and postoperative course after first-stage palliation of HLHS with the bPAB compared with the Norwood procedure with RV-PA. Retrospective review of 27 infants with HLHS who had undergone either the Norwood procedure with RV-PA (n = 15) or the bPAB (n = 12). Hemodynamic data were obtained during cardiac catheterization before and after second-stage palliations (Glenn procedure). Sixteen infants had undergone second-stage palliations [RV-PA; n = 7 (47%), bPAB; n = 9 (75%)]. Before second-stage palliations, right atrial pressure (RV-PA/bPAB) (6.0 ± 3.8/4.8 ± 1.6 mmHg) and RV end-diastolic pressure (8.5 ± 3.9/6.0 ± 1.9 mmHg) were lower in patients who underwent bPAB. RV end-diastolic volume (% of normal) was smaller in the group bPAB (220 ± 40/191 ± 43). RV ejection fraction was similar in both groups (47 ± 8.7/51 ± 11.2%). Arterial oxygen saturation was higher in the group bPAB (63.9 ± 10.2/73.7 ± 4.4%). After second-stage palliations, there were no significant differences in hemodynamic data between the two groups. Our observations indicate that, in patients with HLHS after first-stage palliation, the bPAB procedure may provide a more favorable hemodynamic profile before second-stage palliation. We need further investigations for the hemodynamics after second-stage palliations and after Fontan completion.