Enhancing　the　temperature　distribution　uniformity　in　membrane　electrodes　is　crucial　for　improving　the　durability　and　performance　stability　of　proton　exchange　membrane　fuel　cells.　In　this　study,　we　discovered　an　entrance　region　in　the　cathode　membrane　electrode　of　proton　exchange　membrane　fuel　cells　characterized　by　a　rapid　rise　in　temperature.　This　inlet　region　shows　a　notably　higher　temperature　variation　rate　compared　to　other　regions.　This　phenomenon　is　attributed　to　the　temperature　difference　between　the　constant　temperature　fluid　supplied　by　the　channel　inlet　and　the　heat　generation　in　the　cathode　catalyst　layer.　Thus,　the　impact　of　channel　structure　at　the　entrance　region　on　the　temperature　distribution　of　the　cathode　catalyst　layer　is　investigated,　based　on　a　three-dimensional,　non-isothermal,　two-phase　model.　Results　show　that　boosting　heat　transfer　in　the　inlet　region　is　more　effective　for　reducing　the　average　temperature　than　in　other　regions.　We　proposed　five　kinds　of　step　arrangement　schemes　and　discovered　that　the　step　arrangement　in　the　entrance　region　of　the　cathode　flow　channel　can　increase　the　temperature　uniformity　of　the　cathode　catalyst　layer　by　9.71%　without　net　power　loss.　Furthermore,　this　study　examines　the　impact　of　length,　height　of　entrance　steps,　and　outlet　channel　height　on　heat　transfer　and　identifies　the　optimum　value.　When　severe　water　flooding　occurs,　the　gas　purge　coupled　with　the　step-fronted　scheme　is　essential　for　improving　temperature　uniformity.　©　2024