Objective: To investigate the prognosis of osteosarcoma patients with lung metastases and its correlated factors. Methods: The clinical data of 104 osteosarcoma patients with lung metastasis from April 2007 to September 2015 were retrospectively analyzed. Univariate analysis was performed using Kaplan-Meier and Log rank test. Multivariate Cox regression was applied to analyze independent prognostic factor for patient survival. Results: The one-year, two-year and five-year survival rates of the 104 osteosarcoma patients with lung pulmonary metastasis were 93.3%, 61.5% and 11.5%, respectively, and the median survival time was 33 months. The univariate analysis revealed that number of lung metastases, objective response of first-line chemotherapy and therapeutic methods for lung metastases were significant prognostic factors for patient survival, whereas gender, age, time to lung metastasis and time to other metastasis were not (P>0.05). The multivariate analysis indicated that number of lung metastases, objective response of first-line chemotherapy and therapeutic methods for lung metastases were independent significant prognostic factors for patient survival. Conclusions The prognosis of osteosarcoma patients with advanced lung metastases and active treatment is better. Surgery and adjuvant chemotherapy could effectively prolong survival time for osteosarcoma patients with pulmonary metastasis.