Our study aimed to describe the efficacy and safety of oral anticoagulation (OAC) use in elderly patients (> or = 80 years-old) with atrial fibrillation (AF) and concomitant anaemia. Data for this study were sourced from AF Research Database (NCT03760874). AF patients aged ≥ 80 who received OAC treatment, both direct oral anticoagulant (DOAC) and vitamin K antagonist (VKA) were selected. Participants were categorized as anaemic and non-anaemic. The primary outcome was the occurrence of overall bleeding. The primary effectiveness outcome was the occurrence of thromboembolic events (a composite of ischemic stroke, transient ischemic attack and systemic embolism). The secondary safety and effectiveness outcomes were major, minor bleedings and mortality, respectively. A total of 958 patients were included in the study, 120 (12.5%) were anaemic; among them, 93 patients (76.6%) were treated with VKAs and 28 (23.3%) with DOAC. Kaplan-Meier curves for major bleedings showed significant differences between anemic- and non-anemic groups (log-rank p = 0.005). In multivariate analysis, among patients on OAC, anaemia was independently associated with major bleeding (HR 2.36; 95% IC 1.2–4.4; p = 0.006), intracranial hemorrhages (HR 3.81; 95% IC 1.35–10.7; p = 0.01) and minor bleedings (HR 2.40; 95%IC 1.1–5.2; p = 0.02); these associations were not confirmed in the DOACs subgroup. No difference in survival was shown between anaemic- and non-anaemic groups and among anaemic patients, between DOAC and VKAs subgroups. Anaemic octogenarians with AF on OAC therapy showed a significantly increased risk of major bleedings, in particular ICH, and mortality compared to non-anaemic.