Fifteen patients with central type early or semi-early lung cancer (including 4 with in situ cancer and 1 with N1 disease) were analyzed with respect to symptoms, sputum cytology, chest roentgenogram, bronchoscopy, surgical procedures and resected specimens. 7 patients had no evidence of disease on the chest roentgenogram (Group I) and 8 demonstrated an abnormal shadow, which was either a segmental (or subsegmental) pneumonia-like shadow or a shadow of a segmental (or subsegmental) atelectasis (Group II). 3 patients in Group I were diagnosed by sputum cytology and had no symptoms. The other patients complained of either hemoptysis, persistent cough or symptoms of pneumonia. All of the patients underwent bronchoscopy, which was successful in localizing their tumors. The findings of this bronchoscopy for central type early lung cancer were (1) surface infiltrative disease, (2) tiny nodules, and (3) nodular tumors. The first two findings tended to be characteristic of the tumors in the Group I patients, and the third finding was peculiar to the Group II patients. More patients in Group I seemed to have early disease than in Group II. The 5-year survival rate of the 15 patients with central type early lung cancer has been 90.9%. They can expect favorable postsurgical survival at present regardless of accompanying variables. We emphasize the importance of chest X-ray findings and bronchoscopic findings in the diagnosis of central type early lung cancer.