Background.Pleuropulmonary blastoma (PPB) is a rare primary embryonal tumor of the lung in children. Three main histological variants of PPB with a possible transformation of type I into type II and III are now described. The prognosis in pleuropulmonary blastoma patients with distant metastases is considered to be unfavorable.Case Report.The article presents the case of type I PPB development in a 14-month-old child followed by the transformation of type I PPB into type II in the setting of relapse with multiple bone metastases. The aim of the article was to provide reliable data on successful treatment and achievement of long-term event-free survival in a PPB patient with multiple bone metastases who underwent intensive chemotherapy and high-dose therapy with autologous hematopoietic stem cell transplantation.Conclusion. The case study demonstrates the possibility for achievement of long-term event-free survival in PPB patients with multiple bone metastases and relapses.