Little is known about the impact of child welfare system-level factors on child mortality as an outcome within foster care. Using data from the Adoption and Foster Care Analysis and Reporting System, 2009-2018, we examined the associations between county-level sociodemographic, foster care performance, and judicial reform characteristics with all-cause mortality rates. Results of random effects negative binomial regression analyses showed that higher proportions of younger children (<1year: IRR = 1.06, 95% CI [1.02, 1.11]; 5-9years: IRR = 1.05, 95% CI [1.01, 1.09]); children of color (i.e., non-Hispanic Asian: IRR = 1.07, 95% CI [1.01, 1.13]; multiracial: IRR = 1.03, 95% CI [1.01, 1.04]; non-Hispanic Black: IRR = 1.02, 95% CI [1.01, 1.02]; Hispanic: IRR = 1.01, 95% CI [1.01, 1.02]); and male children (IRR = 1.10, 95% CI [1.05, 1.15]) were associated with higher mortality risks at the county level. Current class action lawsuits (IRR = 0.79, 95% CI [0.63, 0.99]) and active consent decrees (IRR = 0.77, 95% CI [0.63, 0.94]) were associated with lower mortality risks. None of the foster care performance characteristics (e.g., foster care entry, placement stability, permanency) were associated with mortality risks. These findings have implications for addressing health disparities and reforming foster care systems through programmatic and policy efforts.