Pulmonary siderosis is one kind of pneumoconiosis, occurs from chronic inhalation of iron or iron oxide. Inhaled iron dust is deposited in the intra-alveolar spaces, which leads to radiological changes and respiratory symptoms. It is diagnosed by iron exposure history, radiological changes, and the evidence of intra-alveolar iron deposit. We have experienced a case of pulmonary siderosis which was confirmed by bronchoalveolar lavage and transbronchial lung biopsy, so report it with a review of literature.