Abstract: Objective　To investigate the predictive value of neutrophil to lymphocyte ratio (NLR) combined with high-sensitivity cardiac troponin T (hs-cTnT) for atrial fibrillation (AF) after off-pump coronary artery bypass grafting (OPCAB). Methods　A total of 108 patients who were received OPCAB treatment in our hospital from January 2017 to June 2019 were selected, and they were divided into AF group (n=32) and non AF group (n=76) according to whether AF occurred after operation. The general data, cardiac function, OPCAB perioperative indexes, NLR and hs-cTnT were collected and compared between the two groups. The risk factors of AF after OPCAB were analyzed by multiple Logistic regression. The predictive values of NLR and hs-cTnT on AF after OPCAB were analyzed by receiver operating characteristic (ROC) curve. Results　The age, NYHA cardiac function grade≥grade Ⅲ, left atrial diameter (LAD), NLR, hs-cTnT and mechanical ventilation time of patients were significantly higher in the AF group than those in the non AF group (P＜0.05). Multiple Logistic regression analysis showed that the elevated LAD (OR=3.032, 95%CI: 1.614-5.696), NLR (OR=2.186, 95%CI: 1.171-4.081) and hs-cTnT (OR=2.284, 95%CI: 1.313-3.973) were independent risk factors of AF after OPCAB (P＜0.05). ROC analysis showed that NLR and hs-cTnT had higher predictive values for AF after OPCAB, and the areas under the curve were 0.781 (95%CI: 0.685-0.877) and 0.764 (95%CI: 0.663-0.866). The cut-off values were 3.52 and 13.08 ng/L respectively. The combined analysis of the two could further improve the predictive values, and the area under the curve was 0.846 (95%CI: 0.767-0.925). Conclusion　The combination of NLR and hs-cTnT has a higher clinical value in predicting AF after OPCAB, which has certain clinical application value.