A clinical evaluation was done on a total of 41 cases of primary bronchogenic carcinoma, which came to the department of thoracic surgery, Chonnam University Hospital for the period of 5 years from May 1964, and the various factors led the patients to an inoperable stage were searched. The incidence ratio of male to female was 5.8:1 and the age group of fifty and sixty decade occupied 78% of the total. The subjective symptoms of the patients were cough with or without sputum [83%], chest pain or chest discomfort [76%], and a few incidence of bloody sputum and hemoptysis. The histological findings were 40% of squamous cell carcinoma, 35% of adenocarcinoma and 25% of anaplastic carcinoma, including 5 cases of unclassified bronchogenie carcinoma in scalene biopsy. 12 cases [29%] of a total of 41 cases received thoracotomy, but 8 cases among them were operable and 4 cases inoperable. The rest of 29 cases [71%] could not receive thoracotomy because of the various contraindication. 23 cases [70%] out of inoperable 33 cases had wasted time over 2 months duration for an operation owing to physicians` misdiagnosis of bronchogenic carcinoma as pulmonary tuberculosis, chronic lung abscess, asthma, pleurisy, pneumonia. common cold, neuralgia in order. The delaying factors led the patients to an inoperable stage were physicians misdiagnosis of bronchogenic carcinoma due to non-specific symptoms and signs of the patients, old aged patients dependance on herb medicine, and poor economical condition of the patients.[KTCS 1969;1:13-18]