Introduction: Biliary ascariasis, although uncommon, can lead to infectious complications and severe outcomes. This study reported three patients with biliary ascariasis and who were admitted to a paediatric hospital in Salvador, Brazil. Case reports: Case 1: A 1-year-old boy, with HIV, hospitalised with diarrhoea, fever, pain, and abdominal distension. He underwent an exploratory laparotomy, which showed peritonitis secondary to a perforation of the hepatic duct by ascaris. Case 2: A 3-year-old boy admitted with fever, abdominal pain and jaundice. Imaging examination was suggestive of ascaris in the intrahepatic biliary tract and a hepatic abscess. Case 3: A 7-year-old boy who was hospitalised with a history of abdominal colic, jaundice and fever, with a suggestive image of ascaris in the biliary tract and evolution to sepsis. Discussion: Three cases of biliary ascariasis were reported with severe infectious complications involving peritonitis, hepatic abscess and sepsis. Conclusion: In endemic regions, biliary ascariasis should be considered in cases with jaundice, abdominal pain and fever, due to its morbidity and risk of (C) 2020 The Author(s). Published by Elsevier Ltd on behalf of International Society for Infectious Diseases.