This report describes a patient with a type II Caroli' s disease who developed a gallstone ileus. Previous hepaticojejunostomy operations were thought to have facilitated the migration of stones into the bowel and consequent gallstone ileus. This complication, which was strongly suspected from the clinical history, was diagnosed by ultrasound examination despite the absence of aberrantly located stones on plain abdominal x-ray. Ultrasound is useful in the diagnostic workup of patients with bowel obstruction to confirm obstruction itself, to assess its level, and possibly to identify the cause.