Focal nodular hyperplasia of the liver is a benign disorder usually affecting young women. Its treatment in children is traditionally conservative. Because of its rarity in childhood, its differential diagnosis with other hepatic tumors in children and infants is challenging. We present the case of a 7-month-old infant with large focal nodular hyperplasia affecting the whole left liver lobe. Because of progressive enlargement of the lesion and compression of the portal vein, the baby underwent successful surgical treatment. Different therapeutic options and relative indications are discussed.