Aim To evaluate the predictive value of tenascin-C (TNC) in coronary heart disease (CHD) and coronary atherosclerosis severity. Methods 160 patients with chest pain who had undergone coronary angiography were included. According to the results of the angiography, the patients were divided into two groups:CHD group (n＝90) and non-CHD group (n＝70). The coronary atherosclerosis severity was evaluated by Gensini score, and the CHD patients were divided into three groups:low Gensini score group (n＝39), medium Gensini score group (n＝27), high Gensini score group (n＝24). The levels of serum TNC were compared in each group. Pearson correlation analysis and multivariate linear regression analysis were used to evaluate the correlation between TNC and Gensini score. The predictive value of TNC in patients with coronary heart disease and high Gensini score was analyzed by ROC curve. ResultsThe level of serum TNC in CHD group was significantly higher than that in non-CHD group (P＜0.001), the serum TNC level of high Gensini score group was significantly higher than that of medium Gensini score group, and the serum TNC level of medium Gensini score group was significantly higher than that of low Gensini score group (P＜0.001). Pearson correlation analysis and multivariate linear regression analysis showed that there was a significant positive correlation between the serum TNC level and Gensini score in CHD group (P＜0.001). ROC curve analysis showed that the area under curve (AUC) of TNC for predicting CHD was 0.811 (95%CI:0.768-0.974), and the Cut-off value was 11.94 μg/L, the sensitivity and specificity were 83.5% and 76.4% respectively. The AUC of TNC in predicting patients with high Gensini score was 0.944 (95%CI:0.816-0.989), and the Cut-off value was 16.47 μg/L, the sensitivity and specificity were 82.6% and 78.4% respectively. Conclusion Serum TNC level is significantly correlated with Gensini score of CHD patients, which has a certain predictive value for CHD and coronary atherosclerosis severity.