Although significant atrioventricular valve regurgitation (AVVR) is well known for its association with increased morbidity and mortality in patients with single-ventricle physiology, there is a lack of consensus in management of AVVR. The purpose of this study was to analyze the clinical outcomes in patients receiving AVV repair or replacement. From 2001 to 2010, a total of 33 patients (25 male and 8 female) with more than moderate-degree AVVR among 160 patients who underwent staged single-ventricle palliation were included. The median follow-up duration was 6.0 years (range 0.1-14.1). Valve repair (n = 27) or valve replacement (n = 6) was performed at the initial surgery. There were six late mortalities (18.18 %): five in the repair group and one in the replacement group and seven morbidities. Among patients with valve repair, 11 were required to undergo redo-valve operations (valve repair n = 6, valve replacement n = 5) due to deteriorated valve function. Initial shunt procedure (p = 0.04) and arrhythmia (p = 0.01) were risk factors for survival. Freedom from reoperation in the valve replacement group was higher than that in the valve repair group (67.0 ± 9.7 and 44.6 ± 11.2 % at 5 and 6 years, respectively, p = 0.03). Need for early repair (p = 0.02), presence of mitral- or tricuspid-dominant AVV (p = 0.005), and male sex (p = 0.04) were risk factors for valve durability. Early valve regurgitation affects valve durability. Thus, successful repair in the early stage may improve later outcomes. Therefore, aggressive valve surgery was required and AVV replacement might be one of the options for selected patients.