Aortic root dilatation is present by the age of five years in approximately 35% of patients suffering from Marfan syndrome. However, children rarely undergo surgery for aortic aneurysm and aortic regurgitation during their first decade of life. A nine-year-old boy, who presented with severe aortic regurgitation associated with a 76.8 mm aneurysm of the ascending aorta, underwent a Bentall procedure. Since the aortic annulus was markedly dilated and the cusps were structurally abnormal, the aortic valve was not spared.