The aneurysm of iliac artery is a rare entity and there are few computational models that have studied the disease. In this study, we have presented the presented the flow patterns in the aneurysmal artery using Fluid Structure Interaction method. The blood was assumed Newotonian, pulsatile, laminar, incompressible, and homogenous. The geometry of the model was made based on CT images of clinical cases. Using the computational method, we have obtained the velocity and pressure contours, shear rates, and vortices values for the healthy and aneurysmal artery. The results show that vortices formed in the aneurysmal area along with increase of shear rates especially in the neck of aneurysm. Furthermore, the aneurysm with bigger dilation tend to rapture due to more shear rates in the neck. Our results were compared to the literature and were in good agreement.