Objective To investigate the role of renal nerve in cardioprotection provided by renal ischemic preconditioning(RIP).Methods The effects of ischemia-reperfusion and RIP on the hemodynamics, myocardial oxygen consumption, epicardial electrography and infarct size were examined in anesthetized rabbit.Results During the 45 min of myocardial ischemia and 180 min of reperfusion, all hemodynamic parameters and myocardial oxygen consumption decreased progressively significantly. Epicardial electrographic ST-segment was elevated significantly during myocardial ischemia and return to baseline progressively in the course of reperfusion. The myocardial infarct size occupied 55.80±1.25% of area at risk,and RIP significantly reduced the myocardial infarct size to 36.51±2.80%(P＜0.01). The renal nerve section (RNS) per se didn't affect myocardial infarct size produced by ischemia-reperfusion, while cardioprotection afforded by RIP was completely abolished by RNS.Conlusion RIP have the protective effect on heart, and activation of renal afferents by transient ischemia-reperfusion play an important role in such a cardioprotection.