Pleural amyloidosis has been reported rarely, and the diagnosis of this disease by Cope needle biopsy has, to our knowledge, been reported only once previously. We report two patients in whom the diagnosis of pleural amyloidosis was made by biopsy specimens obtained in the examination of large, unilateral pleural effusions. In one patient, the diagnosis was made by Cope needle biopsy. The clinical and diagnostic significance of these cases are discussed.