OBJECTIVE: To observe the changes of chest imaging and prognosis in pneumoconiosis patients in tin smelting workers. METHODS: Ten pneumoconiosis patients working with tin smelting were examined by chest X-ray,computed tomography( CT) photography and dynamic observation on pulmonary imaging to analyze their characteristics and prognosis. RESULTS: There were mild clinical manifestations and no tuberculosis in these 10 cases of tin smelting pneumoconiosis patients. There was no obvious change on the pulmonary ventilation function change. The high k V X-ray chest observation results showed that the circular shadow was the primary small shadow of the two lungs,that were mostly distributed in the medium and upper lung zones of both lungs. In most cases,we found lung texture distortion,deformation or increase,blurred,hilar shadow increased thickening,lymph node calcification,individualized eggshell. There was no pleural changes and emphysema changes. There was no significant change found in 5-10 years of dynamic observation except for 1 case of increased small shadow. The chest CT examination in 2011 showed 2-5 mm nodular shadows. Among them,we found 7 cases of small nodules from the upper lobe evenly distributed to the middle of the lobe,the lower back lobe of the lungs,lower basal ganglia lesions decreased,lesions were diffuse distribution of the whole lung,and the small nodules in 3 cases. Interval lobular thickening at varying degrees were found in 5 cases,lobular central or apoptotic pulmonary emphysema were found in 4 cases,and 1 case of pulmonary bullae formation was found. The results of chest CT examination in 2016 showed 2 cases of diffuse pulmonary nodules,3 cases of thickening of lobular septum and 2 cases of pulmonary emphysema compared with the CT result in 2011. CONCLUSION: There was no obvious lung small shadow absorption found in tin smelting pneumoconiosis patients after 5 to 10 years of X-ray dynamic observation,and progress of lesions could be seen. CT examination is helpful for follow-up observation in tin smelting pneumoconiosis.