A 53-year-old man was referred to our hospital because of atypical cells in the peripheral blood. Myelodysplastic syndrome (MDS) was diagnosed by bone marrow examination. Since he had a continuous dry cough, high fever, and air space consolidation in both lower lung fields, he was admitted to our hospital for further examination. Infectious disease, autoimmune disease, vasculitis and neoplasms were excluded. A transbronchial lung biopsy (TBLB) was performed at the right S(10), and histopathological examination of the specimen thus obtained suggested an organizing pneumonia (OP) associated with MDS. Oral prednisolone 30 mg was administered daily, and the symptoms and radiographic findings immediately improved. Accurate diagnosis of the pulmonary involvement associated with patients with MDS is sometimes difficult to make. However, either BOOP or OP should be considered as a differential diagnosis in case the patient presents with continuous coughing, high fever, and air space consolidation. Interventional examinations such as TBLB should be conducted to make a histological diagnosis if the patient's condition allows it.