This cross-sectional study examined the effects of socioeconomic status (SES) mobility from childhood to adulthood on psychological and cognitive well-being in African American and non-Hispanic White HIV-positive (HIV+) and HIV-seronegative (HIV-) adults who are part of an ongoing study investigating psychosocial and neurobehavioral effects of HIV. Participants (N = 174, 24.1% female, 59.2% African American, 67.8% HIV+) were categorized into four groups (upward mobility, downward mobility, stable-not-poor, chronic-poverty) based on self-reported childhood and current community SES (which were correlated with objective measures of SES and proxies of childhood SES). SES groups were compared on self-report measures of psychological well-being, subjective executive functioning ratings, and performance across six cognitive domains. Primary analyses were stratified by HIV status. For the HIV+ group, SES mobility was associated with psychological well-being (chronic burden of stress: F(7,101) = 3.17, mean squared error [MSE] = 49.42, p = .030, η2 = 0.14; depressive symptoms: F(7,101) = 4.46, MSE = 70.49, p = .006,η2 = 0.14), subjective ratings of executive dysfunction (F(7,101) = 6.11, MSE = 114.29, p = .001,η2 = 0.18), and objective performance in executive functioning (F(9,99) = 3.22, MSE = 249.52, p = .030, η2 = 0.15) and learning (F(9,99) = 3.01, MSE = 220.52, p = .034, η2 = 0.13). In the control group, SES mobility was associated with chronic stress burden (F(5,49) = 4.677, p = .025, η2 = 0.15); however, no other relationships between SES mobility and outcomes of interest were observed (all p values > .20). In general, downward mobility and chronic poverty were associated with worse ratings across psychological well-being measures and cognitive performance. Findings within the HIV+ group are consistent with previous studies that report downward mobility to be associated with poor psychological outcomes. People living with HIV may be particularly vulnerable to the adverse effects of socioeconomic instability.