Treatment of many inherited disorders of hepatic metabolism is still challenging. Hepatocyte transplantation was done in a 47-year-old woman who had glycogen storage disease type 1a and severe fasting hypoglycaemia. 2 billion viable hepatocytes were infused via an indwelling portal-vein catheter, followed by a triple immunosuppression regimen with mycophenolate mofetil, tacrolimus, and steroids. 9 months after transplantation, on only tacrolimus, she eats a normal diet and can fast for 7 h without experiencing hypoglycaemia. Our results show that hepatocyte transplantation might be an alternative to liver transplantation in glycogen storage disease type 1a.