A total of 1,289 patients with primary lung cancer were surgically treated at our hospital from January 1953 to December 1985. Surgical treatment for T4 lung cancer was studied in 93 patients who had pulmonary resections. The relationships between histologic type, stage, method of resection, curability, nodal involvement, pleural involvement, site of invasion, pleural metastasis, pleural effusion, combination therapy, and the survival rate were analyzed. The survival rate of 93 patients with T4 lung cancer was 17% at 3 years and 7% at 5 years. Three-year survival rate of 39 patients with adenocarcinoma, 34 patients with squamous cell carcinoma, and 9 patients with large cell carcinoma was 7%, 23%, and 14%, respectively. Two-year survival rate of 6 patients with small cell carcinoma was 17%. Four-year survival rate of 14 patients who had complete resection was 33%. On the other hand, four-year survival rate of 77 patients who had incomplete resection was 7%. Three-year survival rate of 6 patients with N0 disease, and 19 patients with N1 disease, 46 patients with N2 disease, and 22 patients with NX disease was 40%, 39%, 0%, and 15%, respectively. Two patients, who had partial resection of the left atrium because carcinoma made an invasion upon it, had survived more than 5 years. All patients with esophageal invasion or tracheal invasion had died within a year. Indications of surgical resection for patients with T4 lung cancer should be limited to patients with N0 and N1 disease. Radical pulmonary resection can be performed in patients who are expected to have complete resection.