Thoracoscopic pleural biopsy is useful when other investigations have not revealed the cause of pleural effusion. We report here a case of rheumatoid pleurisy detected from multilocular pleural effusion mimicking empyema. A 65-year-old man visited our hospital for cough persisting for 1 month and arthralgia for 3 days. He was diagnosed with rheumatoid arthritis after a routine checkup. He had an exudative multilocular pleural effusion with negative cultures. Antibiotic therapy was not effective, and thoracic drainage was not successful because of the multilocular pleural effusion. We then performed diagnostic and therapeutic thoracoscopic pleural decortication. Pathological examination of parietal pleural biopsy specimens revealed only non-specific inflammatory changes. Based on histological and clinical findings, we suspected rheumatoid pleurisy and administered empirical steroid therapy. This therapy produced a complete response and thus the diagnosis of rheumatoid pleurisy was established.