The　present　paper　focuses　on　the　comparative　experimental　operating　characteristics　of　working　fluid　pumps　used　in　the　organic　Rankine　cycle　(ORC)　system　with　R245fa,　including　multistage　centrifugal　pump,　hydraulic　diaphragm　metering　pump,　and　roto-jet　pump.　Effects　of　mass　flow　rate　and　outlet　pressure　are　investigated　systemically　on　the　performance　of　the　three　pumps.　Further　theoretical　studies　are　conducted　on　the　effects　of　various　types　of　working　fluid　pumps　on　the　system　overall　performance,　such　as　exergy　destruction　rate,　back　work　ratio　(BWR),　heat　absorption　rate,　thermal　and　exergy　efficiency,　and　net　power　output.　Results　show　that　the　maximum　actual　efficiency　of　the　three　pumps　can　reach　58.76%,　55.26%,　and　30.51%,　respectively,　when　outlet　pressure　ranges　from　0.4　to　1.1　MPa.　A　significant　difference　was　observed　between　actual　and　theoretical　BWR,　which　illustrates　that　the　pump　power　cannot　be　ignored　and　lower　pump　efficiency　has　a　negative　impact　on　the　increase　in　the　net　power　output　of　the　ORC　system.　Additionally,　the　selection　of　working　fluid　pumps　has　significant　effects　on　the　heat　absorption　rate.　Consequently,　the　paper　provides　detailed　and　valuable　insights　into　the　selection　of　working　fluid　pumps　for　the　ORC　system　with　different　heat　capacities.