A male in his 70s was admitted to our hospital with symptoms of ileus. Contrast-enhanced computed tomography confirmed the wall thickness of the sigmoid colon and a small mass in the area of the pancreatic head. Surgical treatment was performed with a preoperative diagnosis of cancer of the sigmoid colon. We examined the pancreatic lesion after the surgical operation. Transabdominal ultrasonography could not detect the pancreatic lesion. Endoscopic ultrasonography identified a solid, rounded, well-demarcated low echoic lesion, measuring 5 mm in diameter on the pancreatic head and third portion of the duodenum. Color Doppler EUS demonstrated no blood flow in the lesion. Therefore, contrast-enhanced color Doppler EUS, using a second-generation contrast agent, showed strong blood flow in the lesion with pulsatile branch vessel. 3D-angiography from computed tomography revealed a pancreaticoduodenal artery aneurysm. We performed preventive transcatheter arterial aneurysm coil embolization. Contrast-enhanced color Doppler EUS is useful for a small pancreaticoduodenal artery aneurysm.