Hepatopulmonary syndrome (HPS) is a clinical state defined by a chronic hepatic disorder, intrapulmonary vascular dilatation, and altered gas exchange resulting in hypoxemia. Cirrhosis of the liver is the most common condition associated with HPS. A 3-year-old boy who presented with end-stage liver disease and severe hepatopulmonary syndrome underwent orthotopic liver transplantation (OLT). The findings of HPS resolved immediately after OLT. His status is within normal limits at 6 months after liver transplantation.