Objective：To explore the method of establishing the bi-directional fluid-solid coupled numerical model based on different thicknesses of aneurysms and arterial wall. Methods：The data series of aneurysm in a patient were got by computed tomography an－giography（CTA） image data. The data series were processed to obtain a surface model of the aneurysm’s vessel segment using MIM－ICS 16.0. The surface model was imported into Geomagic Studio 12.0 and UGS NX 8.5，which were processed to get the bi-directional fluid-solid coupled numerical model of aneurysm. ANSYS Workbench 15.0 software was used to calculate and to evaluate the charac－teristics of intratumoral blood and the stress and strain that Aneurysm wall suffered. Results：The bi-directional fluid-solid coupled model of aneurysm was established successfully and accurately，and it also clearly simulated the blood flow of the intracranial aneurysm，the deformation of the solid wall and velocity of flow lines in a cardiac cycle. Conclusion：Using the above method，the bi-directional fluid-solid coupled model of the aneurysm is established quickly and accurately，which is more accurate and useful than the rigid model and the same thickness aneurysm model. It can also provide excellent model parameters for simulating study of inter－ventional therapy of aneurysm.