A 73-year-old woman with ureteral cancer and multiple systemic metastasis was admitted complaining of dyspnea on exertion after administration of recombinant human tumor necrosis factor (rH-TNF). On chest examination, coarse crackles were heard during inspiration throughout the lungs. Chest roentgenogram revealed a ground glass infiltration, an air bronchogram in the right lung field and an ill-defined right pulmonary artery. Her symptom and chest roentgenological finding improved and coarse crackles were not heard after discontinuation of rH-TNF. Neutrophils and lymphocytes of bronchoalveolar lavage fluid increased and transbronchial lung biopsy specimens showed slight thickening of alveolar septa with infiltration of inflammatory cells. The pulmonary edema was thought to be caused by rH-TNF which induces adherence of neutrophils to endothelium and stimulates them to increase lysosomal enzyme release and oxygen radical production. As a results, it is thought pulmonary permeability might be increased.