From 1979 to 1982, 80 patients with unresectable non-small-cell lung cancer without metastasis were treated with high-dose radiotherapy to the primary and to regional lymph nodes with or without supraclavicular lymphatics in the Department of Therapeutic Radiology, Seoul National University Hospital. Of these, 56 patients$(70\%)$ were completely evaluable, and 59 patients$(74\%)$ had squamous cell carcinoma, 13a large cell undifferentiated carcinoma and 831 adenocarcinoma. 21 patients$(26\%)$ had Stage II and 59 patients$(74\%)$ had Stage III. The complete and partial response rate in the high-dose$(approx;6,000;rad)$ radiotherapy was $70\%;with;19\%$ complete response. 69 patients$(86\%)$ failed in the treatment, by the failure pattern, $64\%$ had local failure alone, $35\%$ had local failure and distant metastasis and $1\%$ had distant metastasis alone. The failure rate in the thorax were $76\%$ in squamous cell carcinoma, $40\%$in adenocarcinoma and $20\%$ in large cell undifferentiated carcinoma Preliminary result shows that actuarial survival at 1, 2 and 3 years were $56\%,;26\%;and;20\%$ in overall patients and $64\%,;37\%;and;21\%;in;Stage;II;and;54\%1,;21\%;and;18\%$ in Stage III, respectively. Overall median survival was 14 months; 17 months in Stage II and 13 months in Stage m. 8 patients$(10\%)$ have lived a minimum of 2 years with no evidence of disease. There was no fatal complication confirmed to be induced by radiotherapy, so definitive high-dose radiotherapy was tolerated well without major problems and resulted in good local control and survival.