Objective To study the standards and safety of low intensity warfarin anticoagulation therapy in elderly patients after heart valve replacement.Methods Three hundred and fifty-six patients (203 males and 153 females) aged 60-73 (64.3±5.1) years who underwent heart valve replacement in our hospital from January 2004 to June 2014 were divided into aorta valve replacement (AVR) group (n =101),mitral valve replacement (MVR) gro up (n =164),and combined AV and MV replacement group (DVR,n =91) according to their surgical procedure,and further divided into INR ＜1.6 group (n=19),1.6≤INR≤2.5 group (n=299),and INR＞2.5 group (n=38)according to their INR.The INR and incidence of thrombosis and hemorrhage were recorded during the follow-up period.Results Thrombosis occured in 5 patients (1.4％),hemorrhage was found in 49 patients (13.8％),the INR was 1.6-2.5 in the patients included in this study.No significant difference was found in the incidence of hemorrhage in AVR,MVR and DVR groups.The incidence of hemorrhage was significantly different in INR＜1.6 group,1.6≤INR≤2.5 group,and INR＞2.5 group.Conclusion Oral warfarin at the mainteinance dose of 1.6-2.5 can achieve its satisfactory anticoagulant effect in old patients after heart valve replacement.