To use coronary CT angiography (CCTA) and invasive coronary angiography (ICA) analyze and evaluate the characteristics of coronary artery plaques in patients with coronary heart disease and explore the correlation with myocardial ischemic injury in patients with coronary heart disease. Methods 70 patients with clinically suspected or confirmed coronary heart disease admitted to the hospital were selected from June 2018 to December 2020. The patients received CCTA and ICA. The differences in the diagnosis of coronary artery stenosis between the two examination methods were compared. According to the fractional flow reserve (FFR) value by ICA examination, the patients were divided into myocardial ischemic injury group (FFR＜0.8, n=39) and non-myocardial ischemic injury group (FFR≥0.8, n=31). The CCTA examination plaque characteristic parameters of calcification score, total plaque volume, calcification plaque volume, plaque load, reconstruction index and lesion length were compared between the two groups. Logistic regression analysis was used to analyze the relationship between plaque characteristic parameters of CCTA and myocardial ischemic injury. Results Among the 556 coronary artery segments detected, CCTA diagnosed mild, moderate, and severe coronary artery stenosis at 147, 52, and 28 segments respectively, and ICA diagnosed mild, moderate, and severe stenosis at 94, 57 and 54 segments respectively, CCTA and ICA had good consistency in diagnosing coronary artery stenosis(Kappa value=0.864, P＞0.05). The accuracy, sensitivity, specificity, positive predictive value and negative predictive value of CCTA in diagnosing coronary artery stenosis at the coronary segment level were 93.53% (520/556), 96.59% (198/205), 91.74% (322/351), 87.22% (198/227) and 97.87% (322/329) respectively. The calcification score, total plaque volume, plaque load, reconstruction index and lesion length in myocardial ischemic injury group were significantly higher than those in non-myocardial ischemic injury group (P＜0.05). There was no statistically significant difference in calcification plaque volume between the two groups of patients (P＞0.05). Multivariate Logistic regression analysis showed that calcification score and lesion length were risk factors for myocardial ischemic injury (P＜0.05).Conclusion CCTA can not only effectively assess the degree of coronary artery stenosis in patients with coronary heart disease, but also analyze the characteristics of coronary artery plaques, and each plaque characteristic parameter can reflect the myocardial ischemic injury to a certain extent. In addition, calcification score and lesion length are risk factors affecting myocardial ischemic injury, and they are of great significance for clinical screening of high-risk patients