The American Heart Association has identified metrics of ideal cardiovascular (CV) health known as Life's Simple 7 (LS7). We determined the prospective relationship between the LS7 and the incident atrial fibrillation (AF) in a biracial cohort. The REasons for Geographic And Racial Differences in Stroke (REGARDS) study enrolled non-Hispanic black and white adults 45 years or older. This analysis included 9,576 REGARDS participants (mean age 63 ± 8.4 years; 57% women; 30% black) who were free of AF at baseline and completed a follow-up examination 9.4 years later. An overall LS7 score was calculated at baseline as the sum of the LS7 component scores and classified as inadequate (0 to 4), average (5 to 9), or optimal (10 to 14) CV health. The primary outcome was incident AF, identified at follow-up by either electrocardiogram or a self-reported medical history of a physician diagnosis. A total of 725 incident AF cases were detected. Compared with the inadequate category (n = 534), participants in the optimal category (n = 1,953) had a 32% lower odds of developing AF (odds ratio 0.68; 95% confidence interval 0.47, 0.99) in a logistic regression model adjusted for demographic characteristics, alcohol use, left ventricular hypertrophy, coronary heart disease, and stroke. A 1-point higher LS7 score was associated with a 5% lower odds of incident AF (odds ratio = 0.95; 95% confidence interval 0.91, 0.99). In conclusion, better CV health, as defined by the LS7 score, is associated with a reduction in development of AF.