〔Abstract〕 Objective To compare the efficacy of different intensity anticoagulation in the treatment of non valvular chronic atrial fibrillation in the elderly. Methods Selected 60 elderly patients with non-valvular chronic atrial fibrillation admitted to Dongxiang District People's Hospital of Fuzhou from October 2018 to December 2019. All patients were given anticoagulation therapy, and the patients were divided into observation group and control group according to different anticoagulation strengths each group has 30 cases. Patients in the observation group were treated with standard anticoagulant intensity [International normalized ratio (INR) 2.00 ~ 2.50] warfarin, and patients in the control group were treated with low anticoagulant intensity (INR 1.50 ~ 2.00) warfarin. The therapeutic effects of the two groups and the occurrence of adverse events were observed. Results The levels of D-dimer, prothrombin time (PT) and activated partial thromboplastin time (APTT) in the observation group were significantly lower than those in the control group (P < 0.05); The incidence of thromboembolism and bleeding in the observation group was lower than that in the control group (P < 0.05). Conclusion Warfarin with standard anticoagulant intensity (2.00 ~ 2.50) is better than low anticoagulant intensity in the treatment of chronic atrial fibrillation in elderly patients with non-valvular disease, and can reduce the risk of adverse events.