Fluid-structure interaction studies were performed on various abdominal aortic aneurysm (AAA) models under the pulsatile flow condition. Eight aneurysm models were made with four different dilatation sizes and two different wall thickness. Stresses and deformations of the aneurysm wall were significantly affected by the dilatation size as well as the wall thickness. The change in wall thickness increased with the more dilated aneurysm. In spite of considerable radial deformations, axial deformations of the aneurysm wall were dominant. The present study showed the strong possibility to understand fluid-structure interactions in the human cardiovascular system.