Abstract: AIM To investigate the effect on heart rate variability (HRV) and heart function of emergency and selective PCI in patients with acute myocardial infarction (AMI). METHODS One hundred and twenty patients with AMI were divided into emergency PCI group (n=42) and elective PCI group (n=38) and control group without receiving any coronary artery reperfusion (n=40). HRV and left ventricular ejection fraction (LVEF), respectively, measured with dynamic electrocardiogram and echocardiography, were applied to observe all cases at 1 and 6 months after AMI. RESULTS There are significant differences between receiving PCI group and control group for HRV and LVEF at 1 and 6 months after AMI. Compared with control group, HRV time domain indexes (SDNN, SDANN, rMSSD, PNN50) and LVEF improve in PCI group. Emergency PCI group is more significant than selective PCI group (P<0.05, P<0.01). CONCLUSION SBoth emergency and selective PCI therapy can improve HRV and heart function in patients with AMI. Emergency PCI is more significant.