Authors studied on the radiological findings of chest radiographs of 1,028 welders engaged at the shipyard in Pusan from January 1st, 1985 to December 31 th, 1986, and also analyzed the radiologic findings by age, duration of dust exposure, subjective symptoms and other associated abnormal radiologic findings. the results were as follows : 1. Small rounded opacities which suggest pneumoconiosis were noted in 107 cases (10.4%). 2. According to ILO classification of the profusion of small rounded opacities, 49 cases (4.8%) are category 0/1 and 58 cases 95.6%) are category 1/0-2/2. 3. The prevalence rate4 of pneumoconiosis increased significantly as the age and the duration of dust exposure increases. 4. The shape and size of regular opacities in pneumoconiosis were 46.6% of p type, 53.4% of q type, and there was no r type. Large opacities were not found. 5. The prevalence rate of pulmonary tuberculosis was radiologically 2.4% in all subjects, It was higher in pneumoconiosis grou (5.6%) than that of non-pneumoconiosis (2.1%). (P,0.05) 6. The main subjective symptoms were sputum (26.2%) mild dyspnea (14.6%), coughing 912.3%), easy fatigability (8.7%) and chest pain 97.4%). The incidence of mild dyspnea and coughing increased significantly in pneumoconiosis group (P<0.01). The 63..6% of pneumoconiosis and 75.8% of non-pneumoconiosis were asymptomatic.