Insulin resistance (IR) has emerged as a risk factor for coronary artery disease (CAD), but there are currently insufficient data on the association of non-insulin-based IR indexes [triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio, triglyceride and glucose (TyG) index, and metabolic score for IR (METS-IR)] with the postoperative prognosis in patients undergoing coronary artery bypass grafting (CABG). Therefore, the present study aimed to examine the predictive power of the above non-insulin-based IR indexes for postoperative prognosis of CABG patients, and to further compare the predictive power of the three indexes. This study included 1472 consecutive CABG patients from June 2014 to January 2019. These patients were divided into two groups based on major adverse cardiovascular events (MACE): without MACE (n = 1136) and with MACE (n = 336). Formulas were used to calculate TyG index, TG/HDL-C, and METS-IR. The Cox regression was done. The study examined how TyG index, TG/HDL-C, and METS-IR improved model performance. Net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were used to evaluate this. The evaluation of model goodness-of-fit was conducted by employing the Akaike information criterion (AIC), Bayesian information criterion (BIC), and χ