Background: Dual-eligible (DE) patients are insured by both Medicaid and Medicare and are known to have complex medical and social needs. While DE patients with cancer have been shown to be less likely to undergo definitive surgical resection of early stage disease and more likely to be diagnosed at a later stage, they have also been shown to be more likely to adhere to cancer treatment due to lower copays with Medicaid. Lung cancer (LC) is the most common cancer diagnosed in the DE population, but little is known about the outcomes of DE patients with LC compared to non-DE patients. Our study sought to assess the impact of DE status on overall survival in lung cancer patients. Methods: We conducted a cross-sectional secondary analysis of data extracted from the Medicare-SEER database, including Medicare patients diagnosed with LC where complete survival data was available. Patients were defined as “DE” if they were designated as DE status during the month they were diagnosed with LC. Categorical variables were compared between DE and non-DE patients using the chi2 test. A Cox regression analysis was performed to evaluate the association between mortality and dual-eligibility, adjusting for demographic and clinical factors including age, ethnicity, gender, stage at time of diagnosis, type of lung cancer, and place of residence (urban vs. rural). Results: A total of 118,816 patients were included in the analysis, of which 81% were non-DE and 19% were DE. DE patients were more likely than non-DE patients to be female, non-white, younger, have squamous cell carcinoma, and be diagnosed at a later stage (P-values all < 0.001). After adjusting for all demographic and clinical characteristics included in the analysis, the hazard ratio for mortality was 1.243 (95% confidence interval: 1.222-1.264, p < 0.001) for DE patients compared to non-DE patients. Conclusions: DE patients with LC have a significantly higher mortality rate than non-DE patients in the Medicare population after adjusting for confounding factors. Future studies should explore the factors that influence this survival differential and consider targeted interventions at the policy level to improve outcomes in this population.