Background: To determine the risk of death and factors associated with survival in patients with primary pulmonary angiosarcoma(PPA).Methods: All patients diagnosed with small cell lung cancer (SCLC) or PPA between 1975 and 2019 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. A further analysis of the PPA patient cohort was performed to assess the effect of surgery, chemotherapy, and radiotherapy on overall survival (OS). A multivariable analysis using the Cox proportional methods and a survival analysis using the Kaplan-Meier method were adopted.Results: A total of 127,126 patients with SCLC and 117 patients with PPA were identified. The majority of PPA patients were older than 60 years (64.1%), were more male (59.0%), and were predominantly white race (77.8%). The median survival time of PPA was 3.0 months (1.88-4.12 months), which was significantly lower than that of SCLC at 7.0 months (6.94-7.06 months, p < 0.01). The median survival with PPA surgery was 4.0 months (2.37-5.63 months), which was higher than that without surgery but not statistically different (4.0 months vs 3.0 months, aHR,0.80; 95% CI: 0.43-1.47; p = 0.46). Median survival with radiotherapy was higher but not statistically different (6.0 months vs 2.0 months, aHR, 0.79; 95% CI: 0.30-2.09; p = 0.63). Median survival with chemotherapy was significantly higher than in those without chemotherapy (9.0 months vs 1.0 month, aHR, 0.43; 95% CI: 0.23-0.80; p < 0.01).Conclusion: PPA is associated with poor outcomes, it has the same predilection site as SCLC, and chemotherapy significantly improves PPA survival outcomes.