In　older　to　overcome　the　disadvantage　of　the　existing　air　powered　engine,　we　proposed　a　new　air　powered　engine-single　screw　expander,　it　has　many　advantages,　such　as　high　volumetric　efficiency,　simple　configuration,　low　noise　and　long　working　life,　etc.　In　order　to　test　the　performance　of　single　screw　expander,　we　have　established　a　compressed　air　powered　system　based　on　single　screw　expander,　the　experiments　were　conducted　for　different　intake　pressure.　Results　indicate　that　the　output　power　and　total　efficiency　increase　as　the　intake　pressure　increases,　and　gas　consumption　ratio　decreases,　namely　good　dynamic　performance,　good　economic　performance　and　higher　total　efficiency　can　be　obtained　at　high　intake　pressure.