A 62-year-old woman was given a diagnosis of rheumatoid lung in 1993. She began receiving manidipine HCl (10 mg per day) on June 19, 1996 to treat hypertension. The next day fever, coughing and dyspnea developed. She was admitted to our hospital on June 28. A chest radiograph showed diffuse reticulo-nodular shadows in all lung fields and arterial blood gas analysis revealed severe hypoxemia. Administration of manidipine HCl was stopped and treatment with methylprednisolone was started. The symptoms and the radiographic evidence of infiltrates disappeared. A drug lymphocyte stimulation test for manidipine HCl was positive. We know of no previous report of pneumonia caused by manidipine HCl.