The　organic　Rankine　cycle　(ORC)　is　a　popular　technology　used　in　waste　heat　recovery　and　low-grade　heat　utilization,　which　are　two　important　measures　to　solve　the　problems　brought　by　the　energy　crisis.　The　economic　performance　of　ORC　system　is　an　important　factor　affecting　its　application　and　development.　Therefore,　the　economic　analysis　of　ORC　is　of　great　significance.　In　this　study,　R123　and　R245fa,　two　frequently-used　working　fluids　during　the　transition　period,　were　selected　for　calculating　and　analyzing　the　economic　performance　of　an　ORC　used　for　recovery　of　waste　heat　with　a　low　flow　rate　and　medium-low　temperature.　Five　traditional　economic　indicators,　namely　total　cost,　net　earnings,　payback　period,　return　on　investment,　levelized　energy　cost,　and　present　value　of　total　profit　in　system　service　life,　which　is　a　relatively　new　indicator,　were　used　to　establish　the　economic　analysis　model　of　ORC.　The　variation　effects　of　evaporation　temperature,　condensation　temperature　of　working　fluid,　flue　gas　inlet　temperature,　and　mass　flow　rate　of　flue　gas　on　the　above　six　economic　indicators　were　analyzed.　The　results　show　that　the　optimal　evaporation　temperature　of　R123　is　125　degrees　C,　the　optimal　condensation　temperature　is　33　degrees　C,　and　the　optimal　heat　source　temperature　is　217　degrees　C.　For　R245fa,　the　optimal　evaporation　temperature　is　122　degrees　C,　the　optimal　condensation　temperature　is　27　degrees　C,　and　the　optimal　heat　source　temperature　is　177　degrees　C.　The　economic　performance　of　an　ORC　demonstration　project　was　reported　and　used　for　comparison　with　the　estimation　and　analysis.　It　was　found　that　the　single　screw　expander　has　an　excellent　economy　performance,　which　greatly　reduces　the　proportion　of　expander　cost　in　the　ORC　system.