A 58-year-old man with Marfan syndrome visited our clinic for a routine examination. He had undergone a modified Bentall procedure with Carrel patch technique for annuloaortic ectasia 15 years previously. Computed tomography revealed an aneurysm of 43×57 mm in diameter at the right coronary ostium. He underwent resection of the aneurysm and coronary reconstruction using Piehler technique. He was discharged on the 37th postoperative day when his renal function recovered. Although the modified Bentall procedure may improve the surgical outcome, long-term follow-up is important because of various postoperative anastomotic complications in patients with Marfan syndrome.