Ascaris lumbricoides is a worldwide intestinal infestation that may cause various complications. Biliary ascariasis, however, is a rare condition. We describe a child with biliary ascariasis. The patient's clinical symptoms were pain, vomiting and abdominal tenderness, and she was thought to have acute appendicitis. However, laboratory examination revealed high serum alkaline phosphatase and amylase levels, and ultrasonography and percutaneous cholangiography demonstrated biliary ascariasis. The patient was successfully treated with mebendazole and antispasmolytic drugs.