In this thesis, theoretical and computational analyses of the heat exchange in a polymer electrolyte membrane fuel cell (PEMFC) cooling plate are described. Thermal management of the fuels cells is essential to ensure high efficiency, durability, and safety of their applications. PEMFC are generally used as a power supply for vehicles in transportation, but can be extended as a back-up power system for household or corporate needs. Analysis of convective heat transfer of PEMFC cooling plates is considerably important in future optimizations techniques to develop new cooling plate designs. Cooling plates are investigated with a method using entropy generation as a numerical analysis alternative to evaluate the performance of the cooling plate designs in addition to temperature variation, pressure drop and velocity profile. The results obtained for the entropy generation in each designs gave effects of the frictional and thermal components of the entropy on heat transfer of cooling channels, confirmation of previous findings, and thermal and hydrodynamic fully developed regions in cooling plates. Benefits and constraints of each design are discussed followed by possible upgrades on designing cooling plates for better PEMFC performance.