Bochdalek hernia is common in infants and children, but extremely rare is adults. So diagnosis and treatment have been many problems. These are case reports of Bochdalek hernia in adults which were evaluated and corrected at the Department of Thoracic and Cardiovascular Surgery, College of Medicine, Chungnam National University during the past 7 years from June 1976 to August 1983. 1.Among the three cases, one was male and the others were female. 2.At first, they were diagnosed as G-I or respiratory disorders and treated symptomatically. But confirmed with UGI and barium enema. 3.All cases had ipsilateral hypoplasia of entire lung or lower lobe as combined anomaly and corrected as simple closure in two cases, pericardial patch closure in one case. 4.Postoperative course was smooth and uneventful.