The authors made a clinical study of 107 cases of empyema who were treated at Department of Thoracic Surgery of Chungnam National University Hospital during the period of Jan. 1976 through Aug. 1982 and compared the empyema of infant and children with that of adults. Following was the remits: 1. Male was predominant to female with the ratio of 2.5 to 1 and adult to infant was 2.6 to 1. 2. The cardinal symptoms were dyspnea, coughing, chest pain and fever. 3. Positive remit of bacteriological culture study was reported in 57% and the most common causative organism was staphylococcus in infant and childhood, E. coil in adult. 4. Most frequent predisposing factors of thoracic empyema in infant and childhood was pneumonia [53%], and in adult was pulmonary tuberculosis [40%]. 5. Treatment were combined with antibiotics therapy and several surgical procedures for empyema. 24 cases [22.4%] required open thoracotomy. 6. The mortality rate was 7.4% [8/107]. 86 cases [80.4%] were discharged with recovery and improvement.[KTCS 1983;1:171-175]