Abstract: Pulmonary Blastoma is a rare lung composed of immature mesenchyme and/or epithelium that morphologically mimics embryonal pulmonary structure. Three cas-es are reviewed, together with the literature. The prognosis of the tumor is poor, and the clinical course is not readily predicated from histologic appearance. It is nce-essary to distinguished it from (l)Carcinosareoma. (2)Malignaint Mixed Tumor. (3)Pleural Mesotheliome.