Proton Exchange Membrane Fuel Cell (PEMFC) performance is highly dependent on key structural and operational parameters. Among these, the contact resistance between the bipolar plate (BPP) and the gas diffusion layer (GDL), as well as the porosity of the GDL, play critical roles in determining power density. This study aims to develop a comprehensive numerical model to analyze the mechanical interactions at the interfaces between these layers. The model focuses on quantifying contact behavior, including contact area and contact force, under varying conditions. By integrating these mechanical effects into the simulation, the work proposes an optimized interface structure to enhance fuel cell performance. The results provide valuable insights into PEMFC behavior, aiding in the design of more efficient and durable fuel cells. This research contributes to advancing fuel cell technology by addressing critical mechanical factors that influence overall efficiency and reliability.