Purpose: Endovascular treatment (EVT) of intracranial aneurysms requires highly trained physicians and careful pre-therapeutic evaluation of the aneurysm morphology. A realistic interventional neuroradiology simulator would provide procedural and skill training for either educational purpose or pre-therapeutic simulation in complex cases. This work aims at evaluating the clinical realism of a computer-based simulator for the EVT of aneurysms. Material and Methods: A prototype computer-based EVT simulation system was developed and implemented. A silicon vascular phantom (Elastrat, Geneva, Switzerland) as well as two patient data sets were used for the evaluation. A coil adapted to the aneurysm was deployed under fluoroscopy. Then, a simulation was done with the same, as well as larger and smaller coils under the same viewing incidence and was visually assessed and compared to fluoroscopic images. The maximum of coil pressure onto the aneurysm sac was recorded during all simulations. Results: In all cases, simulation with the correct coil showed a realistic coil behaviour and aneurysm filling. As expected, full and stable coiling of the aneurysm was impossible to simulate with too small coils. Protrusions outside the sac were observed with too large coils. In this latter case, the pressure onto the aneurysm wall dramatically increased as compared with the correct coil. Conclusion: A preliminary evaluation of a computer-based EVT simulation system was made on both phantom and patient data. Our report emphasizes the clinical realism of the simulated deployment of coils, in particular with regard to potential hazards related to an inadequate choice of coil.