Objective To determine the effect of percentage of atrial pacing on atrial fibrillation (AF) by observing AF burden in the elderly patients with sick-sinus syndrome (SSS) after dual-chamber pacemakers implantation. Methods A retrospective analysis was performed on 301 patients receiving dual-chamber pacemakers implanted in our center from January 2006 to January 2012. They were followed up for (3.9＋1.8) years, and finally 283 of them were enrolled in this study. The numbers of atrial premature, longest duration of AF, AF burden, and percentages of atrial and ventricular pacing were obtained through the pacemaker during follow-up, and the structure and function of heart were evaluated. The patients were divided into 2 groups according to the percentages of atrial pacing (66% as the median of atrial pacing): the high atrial pacing group (141 cases) and the low atrial pacing group (142 cases). Results When compared with the low atrial pacing group, the high atrial pacing group had significantly lower AF burden (including the longest duration of AF and the median of AF burden), and smaller numbers of atrial premature(both P＜0.05). But no difference was seen in the percentage of ventricular pacing between the 2 groups (P＞0.05). There was no obvious difference in the heart structure and function before and after implantation (P＞0.05). Conclusion High percentage of atrial pacing reduces the burden of AF for the elderly SSS patients implanted with dual-chamber pacemaker.