The research of flow field on Vortex generating body position of vortex flowmeter is focused on twodimensional at present,but the actual flow field is threedimensional model.In view of the fact that the twodimensional simulation can not fully verify the flow field generated by the actual fluid impinging the Vortex generating body. The 3D simulation model was built according to the actual mechanical dimensions of vortex generating body using the numerical simulation software platform Ansys Workbench FLUENT in this dissertation.Then make the mesh subdivision on the simulation model ,and calculate it by NS equation.The comparison between the simulation and the real experiment shows that the actual vortex flow field can be simulated by the FLUENT software .Finally with the help of FLUENT software, the influence of generating body position can be determined by adjusting the the translation of generating body in the condition of different Current Speed but the same probe position,So that the maximum allowed translation position δ of generating body can be accessed.