Bronchoalveolar lavage had been done as the treatment of some diseases such as alveolar proteinsois, bronchiectasis, and severe asthma to remove excessive secretion or mucus. But in the recent decade it has been done as a diagnostic method and a tool to understand and evaluate the pathophysiology of diffuse interstitial lung diseases such as sarcoidosis, pneumoconiosis and hypersensitivity pneumonitis. To analyse the bronchoalveolar fluid, it might be useful to have a standard reference (especially cell counts and differetial count of the cells from bronchoalveolar lavage fluid) of normal person. But it is difficult to study the normal volunteers. We investgated the bronchoalveolar lavage fluid of 48 patients (28 nonsmokers, 20 smokers) who visited Severance Hospital because of minor pulmonary symptoms such as cough and sputum. They did neither complain of dyspnea nor cyanosis, and had normal or unilateral minor lesion on physical examination and chest X-ray. We analysed the recovery rate, viability, total cell count and differential count of the cells in fluid obtained by bronchoalveolar lavage. The following results were obtained: 1) Age ranged from 17 to 72 years-old with the mean age of 36.7; there was no difference of age between the nonsmoker and the smoker gorup. Male to female ratio was 2.43:1 for total group, 1.15:1 for nonsmokers, and 19:1 for smokers. 2) The diagnoses of the patients were undetermined in 41.9%, healed pulmonary tuberculosis in 37.5%, laryngitis or pharyngitis in 10.4% and others in 10.4%. 3) Total cell number of the recovered fluid by bronchoalveolar lavage was significantly higher in male[$9.6{pm}6.2({ imes}10^6)$] than in female[$5.1{pm}3.0({ imes}10^6)$](p<0.05), and there was no significant difference in the total cell number between the smokers and nonsmokers [$9.3{pm}5.8({ imes}10^6)$ vs $7.5{pm}5.8({ imes}10^6)$]. 4) The differential count of the cells from bronchoalveolar lavage fluid had no difference between the nonsmokers and the smokers. 5) There was no correlation between the total cell count and smoking or age. 6) In the smoker group, there was no correlation between the amount of smoking and the total cell count of the bronchoalveolar fluid. In conclusion, it should be careful to regard the patients with symptoms or minor radiologic abnormalities as a control group in bronchoalveolar lavage study and further study of cell analysis in bronchoalveolar lavage will be needed between smoker and nonsmoker in the male and female healthy people.