With technical development of multidetector computed tomography (MDCT), diagnostic accuracy of CT in the evaluation of various aortic diseases has markedly increased. However, there are pitfalls that potentially hamper the proper diagnosis of aortic diseases with MDCT. Radiologists should recognize the various pitfalls and be familiar with the remedies of CT artifact occurring in patients with various aortic diseases. We describe prescriptions which allow prompt diagnosis and appropriate treatment for each aortic disease.