Objective To explore the diagnostic value of 256-slice spiral CT coronary angiography(CTA)in coronary artery stenosis.Methods A total of 168 patients with suspected coronary artery stenosis who were examined in Department of Imaging of Zhongshan Hospital of Traditional Chinese Medicine from January 2020 to December 2021 were selected.All patients underwent 256-slice spiral CTA and coronary angiography(CAG)examination,with CAG examination as the“gold standard”.The situation of coronary artery stenosis detected by 256-slice spiral CTA and CAG and the diagnostic value of 256-slice spiral CTA in coronary artery stenosis were analyzed,and the consistency between 256-slice spiral CTA and CAG was calculated.Results Among 168 suspected patients,137 patients with definite diagnosis of coronary artery stenosis,a total of 1 420 vascular segments were detected.The specificity,accuracy and positive predictive value of 256-slice spiral CTA in the diagnosis of severe stenosis were higher than those of mild and moderate stenosis,and the differences were statistically significant(P＜0.05).The sensitivity,specificity,accuracy,positive predictive value and negative predictive value of 256-slice spiral CTA in the diagnosis of coronary artery stenosis were 94.89%,90.32%,94.05%,97.74% and 80.00%,respectively.Kappa test showed that 256-slice spiral CTA was in good agreement with CAG(Kappa=0.812,P＜0.001).Conclusion 256-slice spiral CTA has high application value in the differential diagnosis of coronary artery stenosis,and it has a strong consistency with CAG in the differential diagnosis of coronary artery stenosis.It can provide a reliable reference for clinical diagnosis and treatment,and is worthy of popularization and application.