Human epicardial adipose tissue (EAT) is a type of visceral adipose tissue functioning as an endocrine organ by secreting hormones and adipocytokines which have an important role in the atherosclerotic process. In this study, we aimed to assess the relationship between EAT measured by dual source multidetector computed tomography (MDCT) and descending thoracic aorta (DTA) atherosclerosis. A total of 148 patients who underwent MDCT for the evaluation of coronary artery disease were enrolled in this study. Thickness of the EAT was measured on contrast enhanced multiplanar reformat images with parasternal short axis view at basal, mid-ventricular and apical levels and horizontal long axis view. The atherosclerotic plaque was scored from 0 to 4 points by the percentage of the luminal surface at the cross sectional area of proximal, mid and distal segments of descending aorta. Among the study population, 84 (56.8%) were male and age was (mean ± standart deviation) 56.9 ± 11.7 years. In patients with critical coronary atherosclerosis, DTA atherosclerosis had a significant relationship with EAT (P = 0.012). Multivariate linear regression analysis revealed that in addition to critical coronary stenosis, age and total epicardial fat thickness were associated with aortic atherosclerosis (β value, 0.058 and 0.035; t value, 4.74 and 2.28, respectively; P < 0.05) after adjustment for traditional cardiovascular risk factors. In this study we demonstrated that atherosclerotic plaque burden of DTA was associated with the amount of EAT thickness among patients with suspected CAD shown by MDCT. Further large scale prospective studies are needed to address the interaction of EAT as well as the mediators of inflammation and adipocytokines with the development of atherosclerotic plaques in aorta and effects on cardiovascular outcomes.