Background: The triglyceride-glucose index (TyG index) is a novel metabolic marker initially used as an indicator of insulin resistance. Recently, its use as a cardiovascular risk factor has been taken into consideration; however, there is a shortage of evidence for its clinical importance. Aims: The study aimed to assess the relationship between the TyG index = ln (fasting triglyceride [mg/dl] x fasting glucose [mg/dl]/2) and the incidence of major adverse cardiovascular events (MACE) at a 1-year follow-up among non-diabetic patients with acute myocardial infarction (MI). In addition, the predictive value of the TyG index concerning all- cause mortality in the study group was evaluated. Methods: For the study, 1340 non-diabetic patients with acute MI (median age, 67 years, 70.4% male) were consecutively enrolled between 2013 and 2019. The fasting lipid profile and the fasting glucose level were assessed within 24 hours of admission. Results: MACE occurred in 8.13 % (n = 109) of the study group, whereas 1-year mortality rate was 14.5% (n = 195). There was no difference in the median TyG index value among patients with and without incidence of MACE at a 1-year follow-up (8.73 [8.36-9.08] vs. 8.81 [8.5-9.17]; P = 0.09). Moreover, the TyG index was not a predictor of these events (P = 0.06). In multivariable regression analysis, only previously diagnosed coronary artery disease (CAD) was an independent predictor of MACE (odds ratio [OR], 1.54; 95% CI, 1.02-2.32; P = 0.03). Finally, the TyG index was not an indicator of all-cause mortality (P = 0.25). Conclusions: The TyG index should not be used as a predictor of MACE and all-cause mortality among non-diabetic patients with MI at a 1-year follow-up.