Pancreaticoduodenal artery pseudoaneurysm is one kind of rare splanchnic artery aneurysm. Hemorrhage from the lesion could be life-threatening. We present a case which color Doppler ultrasound and computed tomography angiography (CTA) only showed pancreatic pseudocyst on the background of chronic pancreatitis at first, but contrast-enhanced ultrasound detected blood flow in the pseudocyst and a pancreaticoduodenal artery pseudoaneurysm was worked up several days after. Finally, the pancreaticoduodenal artery pseudoaneurysm was confirmed by digital subtracted angiography. It might suggest the potential advantage of contrast-enhanced ultrasound in evaluating this kind of disease in comparison of CTA.