A 50-year-old man was admitted to our hospital because diffuse reticulonodular shadows in the bilateral lung fields had deteriorated on chest radiographs during a regular checkup. The bronchoalveolar lavage (BAL) fluid revealed an increase in the total number of cells, including slightly elevated levels of eosinophils and neutrophils. The thoracoscopic lung biopsy specimens showed findings compatible with desquamative interstitial pneumonia (DIP). Corticosteroid therapy was done, and improvement of chest CT findings and pulmonary function were seen. We reviewed the clinical features in seventeen patients with biopsy-proven DIP reported in Japan. All patients have good prognoses and a high frequency of steroid responsiveness. Moreover, many patients were positive for antinuclear antibodies in serological tests, and there was a tendency toward increasing eosinophils in BAL fluids.