Systemic lupus erythematosus (SLE) is a chronic inflammatory disease, rarely complicated with cardiac valvular abnormality or aortic aneurysm. An asymptomatic 40-year-old woman with a 15-year history of SLE developed annuloaortic ectasia and aortic valve regurgitation. She had long been maintained on steroid therapy for the treatment of SLE. Her serum anti-phospholipid antibodies were positive. An enhanced computed tomography revealed a dilated aortic root and ascending aorta (57 mm in diameter). Cardiac ultrasonography demonstrated severe aortic regurgitation. We performed the Bentall procedure using a composite graft with the Carrel patch technique. Histopathological examination of the aortic wall showed cystic medial necrosis without any evidence of vascu-litis. Careful long-term follow-up is mandatory for assessing the risk of later anastomotic dehiscence and pseudoaneurysm formation.