Non-Hodgkin's lymphoma arising in lung comprises 0.5% of primary lung tumor and 3% of extranodal lymphoma. The most common radiographic abnormalities of pulmonary lymphoma include pulmonary nodule and consolidation but hilar lymphadenopathy is rarely observed. Recently we experienced primary pulmonary T-cell lymphoma presenting with bilateral hilar lymphadenopathies and diffuse pulmonary infiltration. A 39-year-old man was admitted to the hospital because of fever, cough, and severe dyspnea. Chest PA obtained on admission revealed bilateral hilar lymphadenopathies and diffuse bilateral pulmonary infiltration. The diagnosis of sarcoidosis was strongly suggested and empirical treatment with corticosteroids resulted in dramatic clinical and radiological improvement for a short time. Eventually, CT-guided lung biopsy was performed and the specimen disclosed primary pulmonary Non-Hodgkin's lymphoma of T-cell origin, diffuse small lymphocytic with focal plasmacytoid differentiation.