This is a report of a 57-year-old Malay lady who presented with recurrent episodes of cholangitis and septicaemia. A dilated biliary tree caused by a stenosing periampullary tumour was found to contain adult round worms. A pancreatico-duodenectomy was performed following biliary decompression. Ascarid worms are a rare cause of cholangitis in malignant biliary obstruction.