This　paper　deals　with　the　performance　analysis　and　optimization　for　irreversible　heat　pumps　working　on　reversed　Brayton　cycle　with　constant-temperature　heat　reservoirs　by　taking　exergetic　efficiency　as　the　optimization　objective　combining　exergy　concept　with　finite-time　thermodynamics　(FTT).　Exergetic　efficiency　is　defined　as　the　ratio　of　rate　of　exergy　output　to　rate　of　exergy　input　of　the　system.　The　irreversibilities　considered　in　the　system　include　heat　resistance　losses　in　the　hot-　and　cold-side　heat　exchangers　and　non-isentropic　losses　in　the　compression　and　expansion　processes.　The　analytical　formulas　of　the　heating　load,　coefficient　of　performance　(COP)　and　exergetic　efficiency　for　the　heat　pumps　are　derived.　The　results　are　compared　with　those　obtained　for　the　traditional　heating　load　and　coefficient　of　performance　objectives.　The　influences　of　the　pressure　ratio　of　the　compressor,　the　allocation　of　heat　exchanger　inventory,　the　temperature　ratio　of　two　reservoirs,　the　effectiveness　of　the　hot-　and　cold-side　heat　exchangers　and　regenerator,　the　efficiencies　of　the　compressor　and　expander,　the　ratio　of　hot-side　heat　reservoir　temperature　to　ambient　temperature,　the　total　heat　exchanger　inventory,　and　the　heat　capacity　rate　of　the　working　fluid　on　the　exergetic　efficiency　of　the　heat　pumps　are　analysed　by　numerical　calculations.　The　results　show　that　the　exergetic　efficiency　optimization　is　an　important　and　effective　criterion　for　the　evaluation　of　an　irreversible　heat　pump　working　on　reversed　Brayton　cycle.