Pulmonary blastoma is a rare malignant tumor of the lung that has been treated primarily with surgery. The effect of combination chemotherapy has not been systematically investigated. Two pediatric cases are reported in whom combination chemotherapy consisting of vincristine, actinomycin-D, cyclophosphamide, cis-platinum, and adriamycin was successfully used. The first case, a 5-year-old boy, underwent incomplete surgical excision of the tumor followed by a 104-week course of combination chemotherapy. The second case is a 3-year-old boy who was initially treated with combination chemotherapy that resulted in an objective response; he subsequently underwent surgical excision. This intensive combination chemotherapy is effective both in inoperable tumors as initial therapy as well as a surgical adjuvant.