Background: There are few studies comparing the clinical outcomes of left main disease (LM group) and non-left main disease (Non-LM group) in patients with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI) with drug-eluting stents (DESs). Methods: A total of 685 patients with AMI undergoing PCI with DESs between 2004 to 2010 were enrolled (non-LM, n=641 versus LM, n=44). In-hospital and 1-year clinical outcomes were compared between two groups. Results: There were no significant differences between the 2 groups, including gender, diabetes mellitus, hypertension, smoking history, hyperlipidemia, previous history of myocardial infarction, left ventricular ejection fraction, lipid profile (triglyceride, LDL, HDL cholesterol) level, maximal CK-MB and troponin I level. However, there was significant difference in age, hemoglobin level, chronic kindey diasease, cardiogenic shock, the number of stent implantation at in-hospital outcomes and in age, hemoglobin level, and the number of stent implantation at 1-year clinical outcomes (table). At in-hospital outcomes, cardiac death was higher in LM group. At 1-year clinical outcomes (follow-up, 94.9%) except in-hospital mortality, total MACE, TVR-MACE, TLR-MACE, Revascularization, and TVR were higher in LM group (table). Conclusions: AMI involving LM is associated with higher in-hospital cardiac death and with higher revascularization at 1-year follow-up, compared with non-LM group.