Abstract: Based on mapping functions, a new method was presented to generate the 2D/3D flow field mesh system. To fit the change of field function density in practical studies, the interpolation formula that can control the mesh density was derived, and the mesh generation for the air flow field around a car by means of these formulas was put forward to verify the effectiveness of the present interpolation formula. Moreover, a new technique was proposed to improve the quality of mesh generation in both circular domain and cylindrical domain by introducing the embedded block. And the minimum angle distribution of the mesh system based on the present technique was statistically analyzed and a comparison with the results by other method was carried out in order to verify the improvement. Finally, the air flow field surrounding a long span membrane structure with complex shape was meshed by the program, and then the mesh system was imported into the Ansys-CFX software to simulate the wind pressure distribution on the structural surface. It was concluded that the presented new mesh generation method is very effective in the mesh generation of the flow field.