Abstract Background: Poor patients often reside in neighborhoods of lower socioeconomic status (SES) with high levels of airborne pollutants. They also have higher mortality from non–small cell lung cancer (NSCLC) than those living in wealthier communities. We investigated whether living in polluted neighborhoods is associated with somatic mutations linked with lower survival rates, i.e., TP53 mutations. Methods: In a retrospective cohort of 478 patients with NSCLC treated at a comprehensive cancer center between 2015 and 2018, we used logistic regression to assess associations between individual demographic and clinical characteristics, including somatic TP53 mutation status and environmental risk factors of annual average particulate matter (PM2.5) levels, and neighborhood SES. Results: 277 patients (58%) had somatic TP53 mutations. Of those, 45% lived in neighborhoods with “moderate” Environmental Protection Agency–defined PM2.5 exposure, compared with 39% of patients without TP53 mutations. We found significant associations between living in neighborhoods with “moderate” versus “good” PM2.5 concentrations and minority population percentage [OR, 1.06; 95% confidence interval (CI), 1.04–1.08]. There was a significant association between presence of TP53 mutations and PM2.5 exposure (moderate versus good: OR, 1.66; 95% CI, 1.02–2.72) after adjusting for patient characteristics, other environmental factors, and neighborhood-level SES. Conclusions: When controlling for individual- and neighborhood-level confounders, we find that the odds of having a TP53-mutated NSCLC are increased in areas with higher PM2.5 exposure. Impact: The link between pollution and aggressive biology may contribute to the increased burden of adverse NSCLC outcomes in individuals living in lower SES neighborhoods.