The present disclosure provides a method of mesh generation for an RTM process, including operations of: obtaining a geometry of a target object; generating a solid mesh of the target object according to the geometry; obtaining material characteristics of the target object; assembling a runner mesh with the solid mesh, wherein the runner mesh has grid dimensions different from those of the solid mesh; determining process parameters of the RTM process; and generating a forecasted result of the RTM process according to the solid mesh, the runner mesh, the process parameters, and the material characteristics. Generating the solid mesh includes operations of: dividing the geometry into modules; generating a first and second modular meshes corresponding to a first and second modules, wherein the second modular mesh abuts the first modular mesh, and the second modular mesh has grid dimensions different from those of the first modular mesh.