Additive manufacturing (AM) technologies are increasingly utilized across diverse industries such as aerospace, mechanical, electronics, and biomedical engineering for the fabrication of complex parts. These technologies enable the creation of three-dimensional (3D) components through a layer-by-layer material deposition process, offering advantages like rapid prototyping, reduced material waste, elimination of additional tooling, and efficient material and component design. However, a key challenge in AM-fabricated parts is the anisotropic nature of their mechanical properties, arising from the process-induced mesostructure despite the use of isotropic raw materials. This research focuses on parts manufactured using fused deposition modeling (FDM), a widely used AM technique, and investigates their material behavior by considering the influence of the mesostructure developed during the fabrication process. The study presents a finite element (FE)-based methodology to characterize the constitutive material behavior of FDM-processed parts. In this approach, the mesostructure of the part is explicitly modeled within the FE framework, and uniaxial tensile test simulations are performed. The elastic moduli of a single lamina are determined through linear analysis, while the strength parameters are evaluated using nonlinear FE simulations. The proposed methodology provides an effective framework for predicting the elastic and strength properties of FDM-fabricated components by accounting for their mesostructural characteristics, thereby enabling improved design and analysis of additively manufactured parts.