BACKGROUND: There is emerging evidence for poor health outcomes among Black people with MS, and Black people with MS may have worse walking performance than White counterparts. PURPOSE: The current study examined if Black participants with MS had slower walking speed (timed 25-foot walk, T25FW) and shorter walking distance (six-minute walk, 6MW) than White participants, and if these differences were accounted for by demographic variables, physical activity, disease/clinical characteristics, and Social Determinants of Health (SDOH). METHOD: The analysis included samples of Black (N = 105) and White (N = 246) participants with MS who completed the T25FW and 6MW, underwent a neurological exam for generating an Expanded Disability Status Scale (EDSS) score, and provided data on demographic variables (i.e., age and gender), physical activity, disease/clinical characteristics (i.e., EDSS and MS type), and SDOH (i.e., insurance and employment status) as part of screening and baseline data collection for a clinical trial of exercise training in MS. RESULTS: The Black participants (1.75±3.82 f/s) had a slower T25FW speed (-1.16 f/s, 95 % CI = -2.23, -0.82) than the White participants (2.91±4.97 f/s). The Black participants (842.3 ± 375.7 f) further had a shorter 6MW distance (-119.2 f, 95 % CI = -213.6, -24.7) than the White participants (961.5 ± 339.9 f). The differences in T25FW speed (-0.22 f/s
95 % CI = -0.40, -0.04) and 6MW distance (-82.2 f
95 % CI = -158.4, -6.0) were attenuated, but still different when controlling for other variables in multivariable analyses. CONCLUSION: Black participants with MS had worse walking performance than the White participants. Our results support future research on examining mobility-focused rehabilitation modalities for improving walking performance in Black people with MS. REGISTRATION: The study was registered on ClinicalTrials.gov on March 19, 2018 (NCT03468868).