Abstract: The rupture of intracranial aneurysms is associated with extremely high mortality and disability rates. Flow diverter stents, characterized by their low-porosity design that modulates the intraluminal hemodynamic environment, have emerged as a core technology in interventional therapy. In this study, numerical simulation approaches were employed, integrated with clinical pulsatile blood flow boundary conditions, to conduct a comparative analysis of the dynamic changes in blood flow velocity, wall shear stress (WSS), and vortex structures in saccular and fusiform aneurysms before and after flow diverter stent implantation. The findings revealed that following stent deployment, the maximum reduction in intrasaccular blood flow velocity reached 57.4%, while the proximal flow velocity in fusiform aneurysms decreased by 57.7%. Intraluminal WSS exhibited a significant decline, with the highest reduction of 59.2%, and the complexity of vortex structures was markedly diminished. Furthermore, through the analysis of changes in hemodynamic parameters and their quantitative assessment pre- and post-stent implantation, this study summarized and discussed the regulatory mechanisms of stents on intraluminal blood flow velocity and WSS, the differential mechanisms underlying the stent's regulatory effects based on aneurysm morphology, and the clinical translational value of dynamic responses throughout the cardiac cycle. These insights provide a theoretical foundation for future clinical interventions.