A successfully-treated case of graft infection after thoracoabdominal aortic repair is reported. A 61-year-old male underwent graft replacement of a Crawford type IV thoracoabdominal aortic aneurysm and developed graft infection due to methicillin-resistant Staphylococcus aureus. After 35 days' open retroperitoneal irrigation, the culture around the graft turned negative, and omental transposition and skin flap transfer were successfully conducted. The long-term open retroperitoneal irrigation could be conducted without significant complications, and it was very effective in controlling the severe infection.