4D Flow MRI were performed for 12 abdominal aortic aneurysm patients who underwent EVAR before and after the treatment. Peak systolic blood flow in the common iliac arteries has significantly increased after EVAR (right: p=0.016, left: p=0.016). The aneurysm might have stored blood like a reservoir in systole and have inhibited the delivery of blood flow to the iliac arteries. The stent placement of EVAR may have repaired the deformed blood flow path and improved the efficiency of blood flow delivery to the periphery. 4D Flow have shown its power for analyzing the hemodynamic effects of EVAR.