Aim of the work: this study aimed to evaluate the coronary artery morphology and myocardial perfusion by single reproducible non-invasive contrast enhanced CT acquisition by using DECT scanners with high sensitivity and specificity as well as high diagnostic accuracy without the need to increase the contrast material or radiation dose. Patients and Methods: this study was done during the period from October 2016 to December ,2017; age was ranged between 42 to 73 years old, were 35 patients with CAD diagnosed by cCTA underwent DECT for assessment of myocardial perfusion. The study included 35 patients referred for DECT myocardial perfusion examination in the Police Authority Hospitals, Radiodiagnosis Department in Cairo after diagnosing by cCTA. Each patient included in the study was subjected to full history taking, reviewing medical sheet, cCTA and CT myocardial perfusion examination. Technique was performed by using Aquilion one dynamic volume 320 detector rows CT, Toshiba Medical System, Tochigi-ken, Japan. Results: our study showed a significant correlation and good agreement between the findings of DECT myocardial perfusion defects and the findings of stenosis and its degree on cCTA on a segmental basis with 83% sensitivity, 87% specificity, 86% accuracy, 74% positive predictive value and 92% negative predictive value. Conclusion: DECT myocardial perfusion has high diagnostic as compared to cCTA as the gold reference standard.