A 23-year-old male working in welding for 8 years was admitted to the hospital with chest pain. A large right pneumothorax with complete lung collapse was seen radiographic ally and a tube thoracostomy performed. At high-resolution computed tomography, multiple bilateral well-marginated nodules with surrounding ground-glass opacity were seen. Welder's lung was considered in this patient because of his work in welding for 8 years with iron dust exposure, multiple nodules with ground-glass opacity were seen on HRCT, and serum ferritin and ferritin levels in bronchoalveolar lavage fluid were elevated. The granules in alveolar macrophages obtained from parenchymal biopsy and bronchoalveolar lavage stained strongly with iron dyes. Following avoiding exposure to welding fumes, the lung lesions disappeared without additional therapeutic interventions after a 3-week period. Welder's lung with associated lung lesions has been described, although complicating pneumothorax is unique to the case presented herein.