A 54-year-old man with a sacral abdominal aortic aneurysm (4cm) complained of lower abdominal pain. An abdominal computed tomographic (CT) scan revealed a 1cm expansion in 2 weeks. The abdominal aorta was replaced with an in situ expanded polytetrafluoroethylene graft. Granulomatous lymphoadenitis was diagnosed in the aneurysm wall by histological examination. The patient's postoperative course was uneventful, and anti-tuberculosis medical drug therapy was given for 6 months.