Energy　saving　and　environment　protection　are　two　important　issues　that　today＇s　automobile　industry　must　emphasize.　Lots　of　heat　energy　waste　with　the　exhaust　gas　when　the　engine　is　running.　If　this　part　of　waste　heat　can　be　recovered,　the　energy　efficiency　will　be　improved.　Thus　plenty　of　energy　can　be　saved　and　the　global　warming　also　can　be　reduced.　In　this　paper,　the　organic　Rankine　cycle　whose　working　fluid　was　R245fa　was　studied.　It　was　adopted　to　recover　the　gasoline　engine　waste　heat.　The　mathematical　model　of　the　organic　Rankine　cycle　was　built　up　in　Matlab　to　search　the　optimized　working　condition.　The　pinch　analysis　method　was　used　to　analyze　the　outlet　temperature　of　the　exhaust　gas.　The　results　indicate　that　organic　Rankine　cycle　is　a　good　way　to　recover　the　gasoline　engine　waste　heat,　especially　in　the　high　load　conditions.　The　temperature　of　the　exhaust　gas　can　be　apparently　decreased.