Atherosclerosis is a prevalent systemic disease, responsible for the greatest number of deaths in developed countries. Clinical events and appropriate treatment depend on the sites involved. Both aortic and carotid atherosclerotic disease may result in grave clinical outcomes; however, the association between these two entities has not been clearly demonstrated yet. We developed a study to look at the association between Abdominal aortic Atherosclerotic Plaque (AAP) and Carotid artery Atherosclerotic Plaque (CAP). A prospective cross-sectional study was performed from March 2011 to April 2012. Consecutive patients who underwent total abdominal Computed Tomography (CT) for several reasons and Ultrasonography (US) of the carotid arteries were included. The independent association between the incidental finding of both AAP and CAP was sought using uni and multivariate analyses. One hundred and eighteen patients were evaluated. AAP was present in 53/118 (44.9%) patients and CAP in 69/118 (58.4%). After performing adjustment by multiple logistic regression with covariables such as sex, smoking, diet, abdominal circumference, Systemic Arterial Hypertension (SAH), diabetes and history of ischemic stroke, we observed that AAP and SAH were associated with CAP, with an OR of 10.75 (CI: 3.95-29.3 and p=0.0001) and 5.65 (CI: 2.06-12.5 and p=0.001), respectively. The presence of AAP at CT scan is strongly associated with CAP at US. In the future, such incidental finding at routine abdominal CT may probably recommend carotid US performance. SAH is also strongly associated with the presence of CAP.