Objective: The purpose of this study is to investigate the effects of renal sympathetic nerve stimulation (RSN-S) and ablation (RSN-A) on atrial effective refractory period (ERP) and AF in normal canine heart. Atrial Fibrillation (AF) is a complex disease and one of the most frequent arrhythmias, especially in elderly patients. Multiple mechanisms are involved including interaction between the autonomic nervous system (ANS), electrophysiological properties of the atria, and vulnerability for AF. Cardiac overload increases the incidence of AF. In lone AF the triggers are in the pulmonary veins. AF caused by underlying disease has different mechanism. Atrial fibrillation (AF) is associated with activity of renin-angiotensin-aldosterone system (RAAS). Reduction in renal noradrenaline spillover could be achieved after renal sympathetic denervation (RSD). Methods: 1) Establish of atrial fibrillation model; 2) Ventricular rate analysis of AF; 3) Statistical analysis. Results: 1) The establishment of atrial fibrillation model; 2) Inducibility and duration of AF; 3) The changes of AERP dispersion. Conclusion: Left RSN-S shortened left atrial ERP, increased ERP dispersion, but did not change right atrial ERP. Bilateral RSN-A produced significant prolongation in both atrial ERP, but did not affect ERP dispersion. The on time of RD effect is at 4 hrs after RD procedure and the RD effect on AF will last for 20 hrs after RD procedure.