In　this　study,　a　two-dimensional,　two-phase,　non-isothermal,　and　un-steady　state　unitized　regenerative　fuel　cell　model　is　established.　The　effect　of　various　operating　conditions　on　the　variation　trend　of　parameters　and　cell　performance　during　mode　switching　from　fuel　cell　to　electrolytic　cell　mode　is　studied　when　using　an　elliptically　shallow　flow　channel.　Three　operating　parameter　conditions　are　discussed,　including　inlet　gas　velocity,　electrolytic　cell　voltage　and　water　supply　velocity.　The　effects　of　various　operating　conditions　on　cell　performance　and　parameters　are　compared.　The　results　show　that　different　operating　conditions　have　different　effects　on　cell　performance.　When　switching　from　fuel　cell　mode　to　electrolytic　cell　mode,　changing　the　stoichiometric　ratio　of　inlet　gas　velocity　does　not　affect　the　cell　performance　after　mode　switching.　The　cell　performance　can　be　improved　gradually　with　the　increase　in　electrolytic　cell　voltage.　Increasing　the　flow　rate　of　liquid　water　can　effectively　speed　up　the　stabilization　time,　however,　the　cell　performance　is　slightly　reduced,　and　it　is　easy　to　accumulate　oxygen　at　the　outlet.