Abstract: In order to alleviate the workload of the mesh-generation, a method of generating prismatic grids for viscous flow simulations using hyperbolic partial differential equations was developed. Traditional hyperbolic structured grid generation method was restated and the new method was expanded based on this. Combining orthogonality of the grid and the cell volume specification, the prismatic grid front was gradually generated away from the body surface. The hyperbolic grid generation equation described in the local grid point coordinate system was used to discretize the equations through the upwind and implicit methods, and GMRES solver was used to solve the linear equations, so as to generate the new front layer. To address the prismatic mesh collisions in recessed cavities, explicit numerical dissipation was added with the assistant of grid sensor functions. And pseudo-Laplacian was used to smooth the grid. This method was applied to complex shapes with sharp edges, deep concave, strictly convex and X38 configuration. And the generated meshes showed excellent orthogonality and smoothness, which indicates that the method in this paper is successful. The prism grid was utilized in the flow solver in order to improve the accuracy and efficiency of simulation. Numerical simulation results were in good agreement with experiments. The method proposed in this paper is suitable and accurate not only for aerodynamic simulation, but also for aerothermal environment simulation.