Introduction: Arterial stiffness, defined as high rigidity of the arterial wall, results from vascular aging, and is associated with cardiovascular disease (CVD) later in the lifespan. The reference standard for central aortic stiffening is carotid-femoral pulse wave velocity (CFPWV). Hypothesis: Higher levels of physical activity are associated with lower levels of aortic stiffness, as measured by CFPWV, among African Americans. Methods: A secondary analysis was conducted on data from 1,226 participants in the Jackson Heart Study (JHS) who underwent arterial tonometry assessment for CFPWV (2011-2016) and had physical activity data available. Physical activity was assessed using a 30-item questionnaire that measured four domains: active living habits, work, home life, and sport/exercise activities. Scores were summed across all domains, with higher scores representing higher physical activity (range = 0-16). Higher CFPWV, measured in meters per second (m/s), indicated increased arterial stiffness. Linear regression models (adjusted for sex and age, and multivariable-adjusted for CVD risk factors) were used to assess the association of physical activity with CFPWV. Results: The sample was 60.3% female with a mean age of 59.02 (SD=10.02). The mean physical activity score was 6.16 (2.27) and mean CFPWV value was 10.3m/s (3.84). There was a significant inverse association between physical activity score and CFPWV across both models. With each 1-unit increase in the total physical activity score, CFPWV was -0.14 m/s lower [95% CI -0.22, -0.06] in the model adjusted for age and sex. In the multivariable adjusted model, the magnitude of the association was similar, B = -0.13, 95% CI [-0.20, -0.05]. Conclusions: In this sample of African Americans, greater physical activity was associated with lower levels of aortic stiffness. Given that aortic stiffness is an independent predictor of CVD, longitudinal investigations of the association between physical activity and CFPWV are needed, including exploring whether physical activity interventions can improve aortic stiffness.