Castleman's disease is uncommon lymphoproliferative disorder as giant lymph node hyperplasia and angiofollicular lymph node hyperplasia. Multicentric variant of Cagtleman's disease, plasma cell type has been, described that has mort generalized lymph node involvement as well as involvement of other organ systems than localized type. Multicentric plasma cell type is frequently accompanied by systemic manifestations, such as weight loss, lowgrade fever and weakness. But the reported cases of pulmonary parenchymal involvement are rare and have almost consisted of hyalinized ganuloma adjacent 13 a bronchus. We report a patient with Castleman's disease of the lung, pathologically proven interstitial pulmonary involvement.