The　gas　flow　channels　inside　unitized　regenerative　fuel　cells　display　obvious　effects　on　relevant　parameter　changing　behaviors　such　as　species　concentration,　electrical　signal　and　thermal　signal　during　mode　switching.　In　previous　study,　detailed　transportation　behaviors　inside　a　cell　constructed　with　streamlined　channels　have　not　been　investigated.　In　our　present　study,　a　two-dimensional,　transient　model　coupling　non-isothermal　characteristics　is　employed　to　study　the　changing　characteristics　of　the　cell　with　typical　streamlined　channel　and　comparatively　analyze　the　channel　structure　impacts　on　the　working　states　inside　the　operating　cell　regions.　The　simulated　results　indicate　that　when　turning　the　mode　from　electrolyzer　to　fuel　cells,　the　changing　response　occupied　time　of　each　parameter　is　required　more,　compared　with　the　stabilizing　procedure　after　entering　the　electrolytic　cell　procedure.　For　different　oxygen-side　channels,　when　reducing　the　channel　depth,　the　current　density　output　is　raised,　and　the　needed　time-span　for　the　stabilizing　the　working　state　is　reduced.　The　present　simulation　results　facilitate　better　understanding　mass　transportation　behaviors　inside　unitized　regenerative　fuel　cells　when　the　mode　switches　from　an　electrolytic　cell　to　fuel　cell.　©　2023　Taylor　&　Francis　Group,　LLC.