Background and Purpose. Growing evidences suggest that cardiac adiposity may play an important role in the development of an unfavorable cardiovascular risk profile. Echocardiographic assessment of pericardial fat thickness has been recently proposed as an important risk factor for cardiovascular disease in diabetes or obese patients. But, whether the cardiac adiposity is associated with coronary atherosclerosis in non-obese patients has not been investigated, We aimed to evaluate whether pericardial adipose tissue is related to coronary atherosclerosis in non-obese patients. Materials and Methods. From December 2006 to June 2007, 558 patients were underwent coronary CT angiography (CCTA) to rule out coronary artery disease. In these patients, the patients whose BMI was over 30 were excluded. Remaining patients were divided into normal and abnormal coronary groups whether the atherosclerotic plaques were found on CCTA. In two groups, we matched the cardiovascular risk factors (age, sex, BMI, smoking, hypertension, diabetes, dyslipidemia, and history of hypertension medication). Finally, 165 patients were included in this study. Atherosclerotic plaques were evaluated in all epicardial segments of coronary arteries and pericardial adipose tissue area at midventricular level was measured by semi-automated method on dedicated workstation. Results. 79 patients were included in normal coronary group (male: 42, female: 37, 55.2 짹 12.8 years) and 86 patients were included in abnormal coronary group (male: 34, female: 52, 56 짹 13 years). Pericardial adipose tissue area was significantly larger in abnormal coronary group than in normal coronary group (18.1 짹 10.2 vs 14.6 짹 8.7 cm짼, p=0.019). The other cardiovascular risk factors were similar in these two groups. Conclusion. In non-obese patients, the pericardial fat is more abundant in patients with coronary atherosclerotic plaque than without. This finding suggests that pericardial adipose tissue may play an independent risk factor for cardiovascular disease and warrants further evaluation.