Objective To investigate the efficacy and safety of new oral anticoagulants(NOACs)rivaroxaban and dabigatran versus warfarin in the treatment of the patients with non-valvular atrial fibrillation combined with diabetes mellitus.Methods A retrospective study was performed on 119 cases of patients with non-valvular atrial fibrillation combined with diabetes mellitus from outpatient and inpatient of the Ninth People's Hospital of Suzhou City from Jan 2019 to June 2021.According to the use of anticoagulants,patients were divided into rivaroxaban 10 mg group(Group A,n=25),rivaroxaban 15 mg group(Group B,n=30),dabigatran group(Group C,n=29),and warfarin group(Group D,n=35).All patients were treated continuously for at least 6 months.The incidence of embolism and bleeding events,the changes of coagulation indicator,blood glucose,liver and kidney function indexes were compared before and after treatment among the four groups.Results Thromboembolic events:1 cases(4.00%)of stoke or thromboembolic events occurred in Group A;2 cases(6.67%)occurred in Group B;2 cases(6.90%)occurred in Group C,and 5 cases(14.28%)occurred in Group D.Bleeding events:1 cases(4.00%)of bleeding events occurred in Group A;1 cases(3.33%)occurred in Group B;2 cases(6.90%)occurred in Group C,and 8 cases(22.85%)occurred in Group D.There was no statistically significant difference among the four groups of stoke or thromboembolic events(P>0.05).The incidence of bleeding events in Group A and B were both statistically lower than Group D(P<0.05),and the risk of bleeding events of Group C was similar to Group D(P>0.05)and there was also no statistically significant difference among Group A,B and C(P>0.05).The activated partial thromboplastin time(APTT)of all patients was significantly prolonged after treatment compared with before treatment(P<0.05),but none of them exceeded the upper limit of the normal value by 2 times.The APTT and international normalized ratio(INR)values of Group A and B,INR values of Group C were all statistically better than those of Group D(P<0.05)after the treatment.There were no statistically significant difference in the comparison of blood glucose,liver and kidney function index as well(P>0.05).Conclusion The new oral anticoagulants rivaroxaban and dabigatran showed similar effects in prevention of stroke or thromboembolic events,but better safety profiles with lower risks of bleeding events compared to warfarin in patients with non-valvular atrial fibrillation combined with diabetes mellitus.Dabigatran is comparable in efficacy and safety when compared with rivaroxaban and deserves to be promoted for clinical use.