We report a case of syphilitic aortitis (SA) associated with severe right coronary ostial stenosis, aortic regurgitation (AR), and annuloaortic ectasia (AAE). A 48-year-old man presented to a regional hospital with easy fatigability and nocturnal dyspnea. Echocardiography revealed Seller's grade 3 AR. A computed tomography scan showed AAE, dilatation of the ascending aorta, and calcification of both coronary ostia. Coronary angiography demonstrated that the left coronary artery was intact ; however, the right coronary artery was obscure. Active syphilis was detected on routine blood tests on admission. Therefore, the patient was started on a course of ampicillin/sulbactam (ABPC/SBT). Subsequently, he underwent the Bentall procedure and coronary artery bypass grafting with the right internal thoracic artery. The intraoperative findings showed degeneration of the aorta and severe right coronary ostial stenosis. The pathological findings of the aortic wall and aortic valve were consistent with SA. The postoperative course was uneventful. The patient continued receiving ABPC/SBT for 3 weeks postoperatively, and was then switched to oral amoxicillin.