Seventeen patients with lung cancer over 80 years were treated surgically from 1983 through 1993 in our department. Thirteen patients were male and four were female. The histology of the tumor was adenocarcinomas, squamous, large and small cell carcinomas, in 9, 6, 1 and 1 cases, respectively. More than single lobectomy was performed in each patient. Unilateral pulmonary occlusion test was applied in patients whose expected contralateral FEV1.0/BSA was less than 800 ml.m2, or expected residual FEV1.0/BSA was less than 850 ml.m-2. Postoperative cardiovascular complications, such as PAT, PAC, PVC or Af, were seen in 9 patients, respiratory problems, namely, sputa retention, retained secretions or atelectasis, in 7 patients. Blood chemistry and hematology were performed for about three weeks after operations, and found increases in serum transaminases, and leukocytosis. However, there were no operative death. We conclude that some patients over 80 years of age are candidates for surgery after careful cardiopulmonary preoperative evaluation.