In　proton　exchange　membrane　fuel　cells,　baffled　flow　channels　enhance　the　reactant　transfer　from　flow　channels　to　gas　diffusion　layers.　However,　the　reactant　transfer　depends　on　both　the　diffusive　transfer　and　convective　transfer,　and　how　the　baffles　in　flow　channels　affect　them　is　still　unknown.　Therefore,　in　this　work,　a　two-dimensional,　two-phase,　nonisothermal,　and　steady-state　model　of　proton　exchange　membrane　fuel　cells　is　developed,　and　these　two　transfer　processes　from　flow　channels　to　gas　diffusion　layers　are　comparatively　studied.　Simulation　results　show　that　first　of　all,　the　reactant　transfer　from　flow　channels　to　gas　diffusion　layers　mainly　depends　on　the　diffusive　transfer.　Therefore,　if　the　desire　is　to　enhance　the　mass　transfer　from　flow　channels　to　gas　diffusion　layers,　the　diffusive　mass　transfer　should　be　enhanced　firstly.　Being　guided　by　this　goal,　a　porous-blocked　baffled　flow　channel　is　developed.　This　flow　channel　design　can　further　enhance　the　reactant　transfer　from　flow　channels　to　gas　diffusion　layers,　and　the　cell　performance　can　be　improved.　Moreover,　when　the　porosities　of　porous　blocks　at　the　front　place　of　flow　channels　are　lower,　the　cell　power　is　also　increased　but　the　pumping　power　can　be　reduced　a　lot.