Background. Cases of lymphocylic interstitial pneumonia associated with Sjogren's syndrome are often be encountered. Case. A 66-year-old woman was referred to our hospital because of dyspnea and cough. This case was given a diagnosis of rheumatoid arthritis and Sjogren's syndrome based on classical clinical features including immunoserological findings. Chest CT showed consolidations in both lower lobes. Because pathological findings in the video-assisted thoracoscopic surgery revealed severe lymphocytic and plasmacytic infiltrates in alveolar septa and lymphoid follicles, the diagnosis was changed to lymphocyiic interstitial pneumonia associated with secondary Sjogren's syndrome. Following corticosteroid therapy, clinical symptoms and radiologic abnorrnalities remitted. Conclusion. We reported a case of lymphocyiic interstitial pneumonia associated with rheumatoid arthritis and secondary Sjogren's syndrome. (JJSRE. 2004;26:517-521)