Resistin is a novel adipokine that is suggested to be involved in inflammatory conditions and atherosclerosis. To investigate the prognostic importance of resistin in acute myocardial infarction (AMI) patients. Resistin levels were measured in a population of 132 patients with AMI, of whom 72 (54%) had a diagnosis of ST elevation myocardial infarction (STEMI), and 60 (46%) had non-ST elevation myocardial infarction (NSTEMI). Thirty-three consecutive subjects who were referred to elective coronary angiography due to chest pain evaluation with normal coronary angiograms served as controls. All patients were followed-up for the occurrence of major adverse cardiac events (MACE). There was a significant increase in serum resistin levels in patients with AMI compared to controls (3.71 ± 4.20 vs. 2.00 ± 1.05, p = 0.001, respectively). However, serum resistin levels were similar in patients with STEMI and NSTEMI. (4.26 ± 5.11 vs. 3.06 ± 2.64, p = 0.49, respectively). The patients with MACE had significantly higher levels of serum resistin levels compared to either the AMI or the control group (6.35 ± 5.47, p = 0.005, respectively). Logistic regression analysis revealed that resistin, left ventricular ejection fraction, and coronary artery bypass graft were independent predictors of MACE in AMI patients (OR = 1.11, 95% CI 1.01-1.22, p = 0.03 and OR = 3.84, 95% CI 1.26-11.71, p = 0.018, respectively). Serum resistin level was increased in patients with AMI and constituted a risk factor for MACE in this group.