Aim To study the efficacy and safety of ibutilide for immediate cardioversion of recent-onset persistent atrial fibrillation (PAF) in elderly patients (＞65 years) with left ventricular dysfunction (LVD). Methods 100 elderly patients of recent-onset PAF with LVD were hospitalized in our department of Cardiology from January 2014 to August 2017, and divided into two groups by random number table method:ibutilide group (50 cases) were treated with ibutilide intravenous injection on conversion, initial dose was 1 mg, slow injection after dilution； amiodarone group (50 cases) were treated with amiodarone intravenous injection on conversion, initial dose was 150 mg, slow injection after dilution. The cardioversion rates were compared between the two groups within 30 min, 60 min, 4 hours and 24 hours, the left ventricular function indexes (LVEDD, LVESD, LVEF and NT-proBNP) were measured before treatment and 48 hours after treatment, and adverse events were recorded in the two groups during the conversion (within 24 hours). Results The cardioversion rates of PAF in the ibutilide group were higher than those in the amiodarone group within 30 min, 60 min, 4 hours and 24 hours (P＜0.01 or P＜0.05), the average cardioversion time of PAF in the ibutilide group were shorter than that in the amiodarone group (t＝－3.232, P＝0.002). QTc average recovery time in the ibutilide group were shorter than that in the amiodarone group (t＝－17.743, P＝0.000). LVEDD, LVESD, LVEF and NT-proBNP were significantly improved in the two groups compared with before treatment and 48 hours after treatment (P＜0.01 or P＜0.05), the ibutilide group improved more significantly (P＜0.01 or P＜0.05). The incidence of short-term adverse reactions in the ibutilide group was lower than that in the amiodarone group (χ²＝4.762, P＝0.029), the duration of adverse events in the ibutilide group were shorter than that in the amiodarone group (P＝－11.622, P＝0.000). Conclusion Compared with amiodarone, ibutilide was used in the treatment of recent-onset PAF in elderly patients with LVD, with rapid onset, high conversion rate, significant improvement in LVD and good safety.