Abstract: Primary pulmonary extraosseous osteosarcoma is an exceedingly rare malignant tumor with a poor prognosis. Most of the lung osteosarcoma patients died within 1 year after symptom onset. Radical resection plays an important role in the treatment of primary pulmonary extraosseous osteosarcoma, while multidisciplinary treatment may also help improve the prognosis. The size of the primary lung tumor is probably the most important prognostic factor.