Hemodynamically induced wall shear stress plays an important role in the progression and rupture of cerebral aneurysms. The current work describes Computational Fluid Dynamics (CFD) simulations in anatomically realistic models of cerebral aneurysms. Twenty two lateral and ten terminal aneurysms models were investigated; the effects of simple stent models as endovascular treatment in one lateral aneurysm model were also reported. The models were obtained from three-dimensional rotational angiographic imaging data and CFD were studied under the same physiologically representative waveform of inflow. The flow was assumed to be laminar, non-Newtonian and incompressible. The CFD models were solved with the finite elements package ADINA. Predictions of velocity field and Wall Shear Stress (WSS) on the aneurysms were compared for the different cases. Linear correlations between the WSS on the aneurysm fundus at peak systole for lateral and terminal aneurysms with a non-dimensional index were found. Additionally, the effects of hypertensive pressure on one aneurysm model are also reported, and the positive effects of simple stent models to reduce the aneurysm inflow and WSS are reported.