The manufacturing technologies have undergone significant innovation at the beginning of this century from the development of science and technology. One of the most important inventions in manufacturing technologies is the creation of additive manufacturing technology. Additive manufacturing technologies allow building of a 3D object by adding ultra-thin layers of 2D cross-sectional slices of materials upon these previous layers. The most crucial effectiveness of additive manufacturing technologies is to fabricate the complex geometry of products. As a result, the lattice structure is used extensively in industrial product design to minimize usage of materials and reduce the weight of products. However, the simulation to investigate the mechanical properties of the lattice structure in the design space of a product has many issues such as calculation time, memory-consuming, etc. Thus, the paper presents a new method to automatically generate a geometric model of the lattice structure in a computer-aided design environment. This model will be used to make a simulation using the finite element method analysis to investigate the mechanical properties of each configuration of the lattice structure.