We aim to reveal the abnormality of plane-wise and segmental WSS in different cardiac phases of patients with Marfan syndrome (MFS) with dilated aorta. MFS group presented lower plane-wise axial WSS than normal group at ascending aorta and descending aorta during systole. In respect of segmental WSS, either in the whole cardiac cycle or during systole, MFS patients demonstrated reduced values at almost all segments in proximal ascending aorta. In conclusion, the quantitative indices of plane-wise and regional WSS clearly differentiate MFS patients from normal controls. Therefore, quantification of WSS can provide promising approaches for patient managements in the future.