Biliary atresia (BA) is an idiopathic, progressive, and fatal disease if untreated. Since Kasai first introduced the operation for BA in 1959, there have been encouraging results in treating this disease. Ascending cholangitis is a frequent and often recurrent complication. It may worsen the prognosis, with an increase in mortality, secondary failure of restoration of bile flow, and possible exacerbation of portal hypertension. For patients who have had restoration of bile flow with a timely portoenterostomy, the recurrence of ascending cholangitis is the single most significant variable pertaining to long-term prognosis. Patients with multiple episodes of ascending cholangitis are more likely to require liver transplantation than those without multiple recurrences. Therefore, the prevention of cholangitis is crucial in the management of patients who have had a Kasai portoenterostomy.