This study presents a micromechanical analysis of injection molded short fiber reinforced composites, emphasizing the impact of microstructure and manufacturing processes on their mechanical performance. The methodology comprises a three-step procedure: material characterization, importing injection molding simulation results, and setting up the mechanical system. Material Designer is utilized to combine micro-mechanical and phenomenological methods for characterizing the homogenized material properties, while experimental data calibrates and validates the model. A case study investigating the mechanical behavior of an electronic component’s plastic casing under static load is provided, illustrating the integration of the micro-mechanical material response computed through Material Designer with fiber orientations from a third-party injection simulation software. This integrated approach accounts for the anisotropic and orientation-dependent properties of short fiber reinforced composites and is mapped into Ansys Mechanical for analysis. The research offers valuable insights for designing and optimizing injection molded short fiber composite components in various applied polymer science applications, highlighting the significance of considering fiber orientation and microstructure to ensure simulation accuracy.