A　small　power　generator　test　system　with　low-temperature　waste　heat　was　built　using　R123　as　working　fluid　and　a　scroll　expander　as　a　power　recovery　machine　on　the　basis　of　the　theory　of　organic　Rankine　cycle.　The　influence　of　the　rotating　speed　of　the　scroll　expander　on　the　system　performance　was　analyzed　at　the　same　inlet　temperature　and　mass　flow　rate　of　heat　source,　and　the　two　different　mass　flow　rates　of　working　fluid.　The　results　show　that　the　suction　pressure　and　the　suction　temperature　of　the　scroll　expander　decreased　but　the　discharge　pressure　and　the　discharge　temperature　increased　with　the　increase　in　the　rotating　speed.　The　power　generated　and　the　total　efficiency　decreased　while　the　volumetric　efficiency　of　the　scroll　expander　increased　with　the　increase　in　the　rotating　speed.　Under　the　two　test　conditions,　the　maximum　power　generated　was　0.66　kW　and　0.62　kW,　respectively;　both　the　maximum　total　efficiencies　were　2.1%;　the　range　of　volumetric　efficiency　was　38.5%-56.5%　and　39.7%-60.0%,　respectively.