Mycotic visceral artery aneurysms are rare diseases. Once ruptured, the outcomes are fatal. We report the case of a 56-year-old man who presented with mycotic celiac artery aneurysm caused by methicillin-resistant Staphylococcus aureus infection of the catheter, which was placed for regional infusion therapy for severe acute pancreatitis. Because the presence of intense adhesion of the retroperitoneum due to pancreatitis made it difficult to perform a conventional graft replacement, we performed a thoracic endovascular aneurysm repair with a saphenous vein graft bypass to superior mesenteric artery (SMA). During the operation, the right common iliac artery and SMA were bypassed using a saphenous vein graft through a median laparotomy. After grafting the stent-graft was deployed covering the celiac axis and SMA ostium. He was discharged on the 50th post-operative day. He remains well without recurrence of the infection.