A celiacomesenteric trunk is an anomaly in which the celiac and superior mesenteric arteries have a common origin from the aorta. This structure accounts for less than 1% of all visceral artery anomalies, and is estimated to have an incidence of 0.25%. Aneurysms involving a celiacomesenteric trunk are exceptionally rare. We herein report our treatment modality for an 82-year-old man with a visceral artery aneurysm involving a celiacomesenteric trunk. The aneurysm was resected, and the superior mesenteric, splenic, and common hepatic arteries were successfully reconstructed.