Pleuropulmonary blastoma (PPB) is a rare, malignant intrathoracic tumor that occurs mostly in children before 5 years old. It consists about 15% of all primary pediatric pulmonary tumors and shows various mesenchymal components. Its presentations are nonspecific and common symptoms include fever, cough, chest pain, respiratory distress, and pulmonary infection. PPB should be considered in the differential diagnosis of solid and cystic lesions of thorax in children. Surgery is the main treatment of PPB that followed by chemotherapy. Radiotherapy has controversial effects on PPB. For recurrent tumors, bone marrow transplant is recommended. Two cases of this rare tumor is reported to increase the awareness about this entity and considering it in differential diagnosis of solid and cystic lesions of thorax in infants and children. The first case initially was treated with vincristine, actinomycin-D, and cyclophosphamide (VAC) regimen. Following relapse, it was scheduled with ifosfamide, vincristine, actinomycin-D and doxorubicin (IVADo) regimen and radiotherapy. Then, autologous stem cell rescue (ASCR) was recommended; but the patient was expired due to progressive disease before considering it. The second case was first treated with ifosfamide and doxorubicin alternate with ifosfamide and etoposide (IDo/ IE regimen). Following relapse, it was scheduled with ifosfamide, carboplatin and etoposide (ICE) chemotherapy regimen and he felt better.