In　this　paper,　a　cascade　refrigeration　system　equipped　with　a　single　-screw　compressor　(SSC-CRS)　is　proposed　and　built　in　order　to　achieve　the　goal　of　high　load　cooling　capacity　under　ultra　-low　temperature　conditions.　Firstly,　the　isentropic　efficiency　curve　of　the　single　-screw　compressor　(SSC)　is　fitted　through　experimental　method　in　response　to　the　characteristics　of　low　suction　temperature　and　large　pressure　ratio　of　the　compressor.　In　addition,　the　analysis　of　SSC-CRS　with　28　refrigerant　pairs　are　made　to　compare　the　coefficient　of　refrigeration　(COP)　and　power　consumption.　On　the　basis　of　the　cascade　system,　the　paper　compares　the　improvement　of　performance　between　two　circuits　with　SSC:　vapor　injection　cascade　refrigeration　system　(SSC-ICRS)　and　ejector　vapor　injection　cascade　refrigeration　system　(SSC-EICRS).　The　results　indicate　the　COP　improvement　rate　of　SSC-ICRS　system　is　17.39　%　-　41.98　%　and　the　COP　improvement　rate　of　SSC-EICRS　system　is　49.46　%　-　68.37　%　compared　with　SSC-CRS.