A system supporting an interventional radiology (IR) procedure is presented in this paper. A 3D geometric modeling method has been developed to construct a 3D vascular model containing complete connection information of cerebral vasculature for IR planning and intra-operative guidance. The validation result proved the fidelity of the reconstructed model. A magnetic tracking system is employed in this project to trace the tip of the IR device, whose model can be displayed onto a 3D digital model in real time. Magnetic tracking of IR device plus the 3D model can potentially help the radiologist more easily manipulate IR device through vasculature. A method following automatic guidance of IR device (such as catheter and guidewire) from the entry to target is proposed, which can reduce the radiation dose and thus benefit both patients and staff.