Cognitive aging and associated functional decline are a growing area of focus due to the rapidly expanding older adult population. There are also known racial differences in the severity of cognitive decline in aging, with Black/African American older adults displaying greater cognitive impairment and greater risk of dementia compared to White older adults. We sought to evaluate these racial differences in the context of important risk factors for cognitive decline, as African Americans tend to display higher levels of negative risk factors for decline, including cardiovascular risk (CVR), while also displaying fewer protective/reserve factors, like higher educational and occupational attainment due to historic socioeconomic disparities. We applied a sequential mediation model to assess the serial effect of cognitive reserve (education and occupational intensity), and CVR on cognitive performance (Chapter 3), white matter hyperintensity volume (WMHs), and diffusion tensor imaging (DTI) metrics (Chapter 4) in a matched sample of Black and White older adults. Our results revealed significant differences in executive performance between Black and White older adults, as well as significant differences in CVR scores across racial groups, with Black participants displaying lower average executive performance and greater CVR. While educational attainment and occupational intensity did not differ across groups, CVR partially mediated the relationship between racial group membership and executive performance. There was significant unexplained variance in this model. There were no significant differences between WMH and DTI metrics across racial groups, however, greater CVR was associated with greater WMH volume. In exploratory DTI analyses, greater CVR was related in some regions with greater white matter integrity (greater anisotropic and less isotropic water movement), but this was based on analyses in a small sample. Our results suggest that racial disparities in CVR partially explain differences in cognitive performance, even though these differences do not appear related to differences in white matter structure. These findings highlight that modifiable risk factors like CVR may be a focus of intervention/prevention, particularly among historically disadvantaged groups, as well as the need to better understand other possible mechanisms that contribute to disparities in cognitive outcomes among racial groups.