Adalimumab is a full human monoclonal antibody that inhibits tumor necrosis factor-alpha (TNF-α). This has recently been shown to be effective in the treatment of rheumatoid arthritis (RA), ankylosing spondylitis, and other conditions. Sacoidosis is known to be the target for adalimumab but we describe a patient who has developed sarcoidosis with lung involvement during adalimumab therapy for RA. A 48-year-old woman, who was treated with adalimumab for 5 months, was admitted because of chronic cough and both hilar lymphadenopathy on chest radiography. Chest computed tomography revealed the enlargement of multiple lymph nodes in the right supraclavicular, subcarinal, both hilar and right axillary area. She was diagnosed with sarcoidosis based on the biopsy of supraclavicular lymph node, skin and lung through video-associated thoracoscopic surgery, which was non-caseating epitheloid cell granuloma and excluded from a similar disease. She was treated for sarcoidosis with prednisolone and methotrexate instead of adalimumab.