In　order　to　find　out　the　influences　of　inlet　parameters　on　the　two-component　mixture　spontaneous　condensation　flows,　and　to　offer　reference　for　industry　application　of　supersonic　separator,　a　mathematical　model　was　developed　to　investigate　the　two-component　mixture　spontaneous　condensation　flow.　A　numerical　simulation　was　performed　for　the　two-component　mixture　in　nozzle　with　the　model.　The　comparison　between　numerical　results　and　experimental　measurement　shows　that　the　model　is　accurate.　With　the　model　the　influence　of　different　inlet　parameters　was　investigated.　It　was　found　the　liquid　mass　fraction　became　higher　with　the　lower　pressure,　higher　temperature　or　higher　supersaturation　at　inlet　for　nozzle　with　certain　expansion　rate　and　length.　It　is　useful　to　change　the　pressure,　temperature　and　supersaturation　at　inlet　properly　to　get　higher　separation　efficiency　in　industry　application.