Hemodynamically induced 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 lateral aneurysms models were investigated. 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 aneurysms with an area index were found.