© 2016 Elsevier, Inc. Background We conducted a retrospective analysis examining the association between systolic blood pressure (SBP) or hypertension bracket and stroke risk in patients with atrial fibrillation (AF). Methods The study included 14,256 anticoagulated patients in the ROCKET AF trial. Cox proportional hazards models were used to compare the risk of adverse outcomes by European Society of Cardiology hypertension bracket and screening SBP. Results In total, 90.5% of patients had hypertension (55.8% controlled, 34.6% uncontrolled). The adjusted risk of stroke or systemic embolism (SE) increased significantly for every 10-mm Hg increase in screening SBP (hazard ratio [HR] 1.07, 95% CI 1.02-1.13). There was a trend toward an increased adjusted risk of stroke or SE in patients with controlled (HR 1.22, 95% CI 0.89-1.66) and uncontrolled hypertension (HR 1.42, 95% CI 1.03-1.95) (P =.06). In contrast, the adjusted risk of major bleeding was similar between hypertensive brackets and did not vary significantly by screening SBP. The benefit of rivaroxaban versus warfarin in preventing stroke or SE was consistent among patients regardless of SBP (P interaction =.69). Conclusions In a trial of anticoagulated patients with AF, increasing screening SBP was independently associated with stroke and SE, and one-third of patients had uncontrolled hypertension. The relative effectiveness and safety of rivaroxaban versus warfarin were consistent across all levels of screening SBP. A single SBP may be an important factor in reducing the overall risk of stroke and SE in anticoagulated patients with AF.