Objective: To evaluate management strategies for acute cholangitis in elderly patients (age, greater than or equal to 80 years). Design: Nonrandomized control trial. Setting: A university hospital. Patients: Patients (n=191) who underwent urgent biliary drainage for acute cholangitis due to choledocholithiasis. Thirty-seven patients were elderly, and 154 were younger (age, <80 years). Interventions: Surgical (8 elderly and 48 younger patients), percutaneous transhepatic (11 elderly and 47 younger patients), or endoscopic drainage (18 elderly and 59 younger patients). Main Outcome Measures: Clinical features of acute cholangitis and outcomes of biliary drainage. Results: The elderly patients had higher incidences of septic shock or mental confusion (acute severe cholangitis) (43.2%) and concomitant diseases (81.1%) than the younger patients (25.3% and 42.9%, respectively). The elderly patients had significantly greater morbidity (37.8%) and mortality (10.8%), compared with the younger patients (16.9% and 3.2%, respectively). Mortality was 18.8% in elderly patients with severe cholangitis and 4.8% in those with nonsevere cholangitis. In the elderly patients, endoscopic drainage yielded lower morbidity (16.7%) and mortality (5.6%) than surgical (87.5% and 25.0%, respectively) and percutaneous drainage (36.4% and 9.1%, respectively). No complications occurred after endoscopic nasobiliary drainage without sphincterotomy. Conclusions: Elderly patients with acute cholangitis have high incidence of severe disease and concomitant medical problems. They should undergo endoscopic biliary drainage, especially nasobiliary drainage without sphincterotomy, because of its safety and effectiveness.