OBJECTIVE： To explore the effect of dabigatran etexilate on coagulation indexes and safety of elderly patients with persistent atrial fibrillation. METHODS： 52 elderly patients with persistent atrial fibrillation were randomly divided into observation group and control group by random number table， 26 cases in each group. Creatinine clearance rate in observation group was higher than 30 ml/min， 110 mg Dabigatran etexilate capsule was orally given， bid； when 15-30 ml/min， 55 mg capsule was orally given， bid. Control group orally received Warfarin sodium tablet with initial dose of 2.5 mg， qd， according to international normalized ratio （INR） after 3-5 days till maintained in 2.0-3.0. After 3 months， coagulation indexes [prothrombin time （PT）， activated partial thromboplastin time （APTT）， thrombin time （TT）， INR， platelet count （PLT）， fibrinogen （FIB）] before and after treatment， incidences of clinical events （cerebral embolism， cerebral hemorrhage， fatal bleeding， the remaining parts of embolism， death） and adverse reactions in 2 groups were compared. RESULTS： There was no significant difference in PT， APTT， TT， PLT and FIB between 2 groups before treatment （P＞0.05）； after treatment， PT and INR in 2 groups significantly increased， and observation group was obviously better than control group， the difference was statistically significant （P＜0.05）. No cerebral hemorrhage or fatal hemorrhage occurred in the two groups. There was no significant difference in the incidence of cerebral embolism between 2 groups （P＞0.05）； the incidence of remaining parts of embolism， death in observation group significantly lower than control group， the difference was statistically significant （P＜0.05）. The incidence of adverse reactions in observation group was significantly lower than control group， the difference was statistically significant （P＜0.05）. CONCLUSIONS： Dabigatran etexilate shows good coagulation effect on elderly patients with persistent atrial fibrillation， which can effectively improve PT and INR levels and reduce the incidences of clinical events， with good safety.