Objective To study the clinical value of selective coronary angiography (CAG) and dual-source CT coronary angiography (CTA) in the diagnosis of coronary artery stenosis. Methods The clinical data of 150 patients with coronary artery disease who were diagnosed in our hospital were analyzed retrospectively. All patients were given dualsource coronary CTA and CAG respectively. The CAG results were used as the gold standard to evaluate the sensitivity, specificity, positive (negative) predictive value and Kappa value (consistency) of dual-source coronary CTA in the screening of abnormal coronary artery stenosis. Results The sensitivity, specificity, accuracy, positive predictive value, negative predictive value and Kappa value of dual-source CTA in the diagnosis of coronary artery stenosis were 0.986, 0.750, 0.967, 0.978, 0.818 and 0.765, and the dualsource CTA and CAG were in good consistency. The sensitivities of dual-source CTA in the diagnosis of mild, moderate, and severe luminal stenosis were 0.985, 0.971 and 0.969, respectively. Conclusion Dual-source coronary CTA has a high accuracy in the diagnosis of abnormal coronary artery stenosis, and it is similar to the results of CAG screening, and it is a safe and reliable non-invasive diagnostic method.