A　comprehensive　exergy　analysis　was　carried　out　for　three　circuits　and　whole　system　of　a　ground　source　heat　pump　(GSHP)　at　the　refrigeration　and　heating　conditions.　The　analytical　formulas　of　exergy　loss,　exergy　efficiency,　exergy　loss　rate,　exergy　loss　coefficient　and　thermodynamic　perfect　degree　were　derived,　respectively.　The　results　show　that　these　exergy　indexes　should　be　used　synthetically,　and　the　maximum　exergy　loss　rate　in　the　whole　system　is　located　in　the　compressor,　while　the　location　of　minimum　exergy　efficiency　and　thermodynamic　perfect　degree　is　the　ground　heat　exchanger.　Therefor,　the　compressor　and　the　ground　heat　exchanger　should　be　improved　primarily.