Thirty-four patients less than 20 years old with acute or chronic cholecystitis were treated in a 12-year period. Recent pregnancy and prior or concurrent urinary tract infections were present in a substantial number of patients, but hematologic disease and anomalies of the biliary tract were relatively infrequent. Ten patients had jaundice at some time during their illness, but none of these was found to have common duct stones. Symptoms and signs of the disease are remarkably similar to those in adults, but unnecessary delay in diagnosis occurred because of failure to suspect the disease in this age group. Cholecystectomy was carried out in each of the 34 patients without mortality or significant morbidity.