Gastrointestinal tract hemorrhage from rupture of the splenic artery into the pancreatic duct is unusual. This obscure cause of intermittent gastrointestinal tract bleeding should be suspected when the more common causes of bleeding have been ruled out. Duodenoscopy carried out during active hemorrhage may reveal blood coming from the papilla of Vater. Coeliac arteriography will show the pathognomonic findings and confirm the diagnosis. We have treated three patients who had chronic pancreatitis and who developed pseudocyst formation and pseudoaneurysms of the splenic artery. The pseudoaneurysm ruptured into the duct of Wirsung, causing obscure upper-gastrointestinal bleeding. Treatment was distal pancreatectomy and splenectomy, including the pseudoaneurysm and pseudocyst. A review of the literature suggests that three different types of bleeding into the pancreatic duct can occur. The cause of each is described.