A 53-year-old man was referred to our facility from another regional hospital where he had been admitted 3 days earlier with a chief complaint of increasing intermittent epigastric pain for the previous 2 weeks. Computed tomography showed a hepatic artery aneurysm, 13 cm in diameter. His vital signs were stable, and surgery was performed. The aneurysm was located on the body of the pancreas. Its right lateral wall compressed and adhered to the common bile duct, and its posterior wall adhered to the portal vein. Its proximal end was at the bifurcation of the celiac artery to the splenic artery, and its distal end was connected to the right and left hepatic arteries. The celiac artery and proximal abdominal aorta were difficult to expose. Therefore, intra-aortic balloon occlusion was performed to control the blood flow to the aneurysm. The wall of the aneurysm was then incised, and the orifice of the common hepatic artery to the aneurysm was closed by suture, followed by saphenous vein grafting from the left gastric artery to the right and left hepatic arteries. The patient was discharged 12 days after surgery with recovery from jaundice. He has been well for 8 years since the operation.