Pancreatic ascites presenting in infancy, with review of the literature. We report a 4-month-old boy with massive ascites in whom a diagnosis of pancreatitis was made on a raised ascitic amylase level after two inconclusive laparotomies. He developed a pseudocyst which was managed with repeated percutaneous needle aspirations, nutrition being maintained intravenously. Endoscopic retrograde cholangiopancreatography (ERCP) demonstrated a congenital intra-pancreatic cyst. He thrived after operation drainage for recurrent pseudocyst, but repeat ERCP shows that the cyst in the head of the pancreas remains. Pancreatic ascites is rare in children and diagnosis is frequently delayed. A third of reported cases in childhood present in the first year of life. A search for the underlying cause should include an ERCP to demonstrate abnormalities of the pancreaticobiliary ducts. 