This study aimed to determine the prevalence and severity of coronary artery disease (CAD) in asymptomatic diabetic and nondiabetic patients using coronary CT angiography (CCTA). The study found CAD was present in 93% of asymptomatic diabetics compared to 73% of nondiabetics. Obstructive CAD was more common in diabetics at 29% versus 6.6% in nondiabetics. Diabetics also had higher total Agatston scores and more coronary segments with atherosclerosis. The results indicate asymptomatic diabetics have a high prevalence of CAD, suggesting CCTA may be useful for evaluating subclinical disease in this high risk group.