An　ecological　performance　analysis　and　optimization　based　on　the　exergetic　analysis　is　carried　out　in　this　paper　for　an　endoreversible　air　heat　pump　cycle　with　variable-temperature　heat　reservoirs.　An　exergy-based　ecological　optimization　criterion,　which　consists　of　maximizing　a　function　representing　the　best　compromise　between　the　exergy　output　rate　and　exergy　loss　rate　(entropy　generation　rate　and　environment　temperature　product)　of　the　heat　pump　cycle,　is　taken　as　the　objective　function.　The　analytical　relation　of　the　exergy-based　ecological　function　is　derived.　The　effects　of　pressure　ratio,　the　effectiveness　of　the　heat　exchangers,　the　inlet　temperature　ratio　of　the　heat　reservoirs　and　the　ratio　of　hot-side　heat　reservoir　inlet　temperature　to　ambient　temperature　on　ecological　function　are　analyzed.　The　cycle　performance　optimizations　are　performed　by　searching　the　optimum　distribution　of　heat　conductance　of　the　hot-　and　cold-side　heat　exchangers　for　fixed　total　heat　exchanger　inventory　and　the　optimum　heat　capacity　rate　matching　between　the　working　fluid　and　the　heat　reservoirs,　respectively.　The　influences　of　some　design　parameters,　including　heat　exchanger　inventory　and　heat　capacity　rate　of　the　working　fluid　on　the　optimal　performance　of　the　endoreversible　air　heat　pump　are　provided　by　numerical　examples.　The　results　show　that　the　exergy-based　ecological　optimization　is　an　important　and　effective　criterion　for　the　evaluation　of　air　heat　pumps.