Multidetector computed tomography (CT) has become the best modality for evaluating an aorta in the acute setting, due to its ability to rapidly detect aortic pathology with high spatial resolution. Moreover, using three-dimensional multiplanar reconstruction, CT scans can provide informative images and accurate measurements of aortic size and other anatomical landmarks. This review focuses on the CT imaging findings of aortic normal anatomy, aortic aneurysm, and the imaging spectrum of acute aortic syndrome, which includes penetrating atherosclerotic ulcer, intramural hematoma, and aortic dissection.