Abstract Background Few data are available on the clinical course of patients with Atrial Fibrillation (AF) and Nonalcoholic Fatty Liver Disease (NAFLD). Purpose To evaluate the 1-year risk of all-cause death, thromboembolic events, and bleeding in AF patients with NAFLD. Methods Retrospective cohort study within the global TriNetX platform. Patients with AF were categorized into two groups: i) AF with NAFLD and ii) AF without liver diseases. The primary outcomes were the 1-year risks of a composite outcome of i) all-cause death and thrombotic events (all-cause death, acute myocardial infarction, ischemic stroke, systemic arterial thromboembolism, deep vein thrombosis, and pulmonary embolism), and hemorrhagic outcome (intracranial hemorrhage and gastrointestinal bleeding). Secondary outcomes were each component of the composite primary outcomes. Cox regression analysis before and after propensity-score-matching (PSM) was used to estimate HR and 95% confidence interval (95%CI). Sensitivity analyses were done to investigate the risk associated with cirrhosis and type of oral anticoagulant. Results We identified 22,636 AF patients with NAFLD (69±12 years, 46.7% females) and 391,014 AF patients without NAFLD (72±12 years, 42.7% females). Before PSM, AF patients with NAFLD were younger, and with a higher prevalence of cardiovascular risk factors than those without liver disease. After PSM, no difference was found between the two groups, but NAFLD patients showed a higher 1-year risk of thrombotic (HR 1.54, 95%CI 1.47-1.61) and hemorrhagic (HR 1.56, 95%CI 1.42-1.72) composite outcomes (Figure 1). The higher risk in NAFLD was consistent also for all the secondary outcomes (Figure 1). On the sensitivity analyses (Figure 2), a progressively increased risk of thrombotic and hemorrhagic events was found in non-cirrhotic and cirrhotic patients compared to patients without liver diseases, whereas non-vitamin-k antagonist (NOAC) seems to be safer and more effective than warfarin. Conclusion In AF patients, NAFLD is associated with a higher 1-year risk of all-cause death, thrombotic and hemorrhagic events. Further studies are needed to establish the best clinical approach to manage NAFLD in AF patients.Figure 1Figure 2