Pulmonary papillary adenomas are very rare benign neoplasms, with approximately 24 cases reported in the English literature. They typically do not contain any more than an occasional focal area of sclerosis. Indeed, sclerotic interstitium within a sclerosing hemangioma has been reported to be a criterion used to distinguish it from pulmonary papillary adenoma. We present a case of pulmonary sclerosing papillary adenoma, with extensive sclerotic stroma and scattered areas containing typical papillary architecture.