Stream　reforming　ethanol　can　not　only　produce　hydrogen　on　board　and　solve　the　problem　of　storage,　but　also　realize　the　mixed　combustion　of　fuel　with　hydrogen-rich　reformed　gas　and　improve　engine　emissions.　To　get　the　optimal　experiment　method,　the　experiment　was　performed　on　a　self-designed　apparatus　that　could　provide　the　similar　temperature　as　the　engine　exhaust　gas.　The　effects　of　reaction　temperature,　water/ethanol　molar　ratio　and　gas　hourly　space　velocity　(GHSV)　on　hydrogen　concentration　in　the　outlet　gases　were　experimentally　investigated　over　Cu49Zn21Al18Zr12　and　Pt/CZO/Al2O3　catalyst.　Results　show　that　hydrogen　productivity　through　steam　reforming　of　ethanol　over　Pt/CZO/Al2O3　catalyst　is　higher　than　Cu49Zn21Al18Zr12　catalyst,　especially　when　the　reaction　temperature　is　up　to　823　K.　The　average　values　of　hydrogen　concentration　are　40.26%　and　47.78%　when　the　reaction　temperature　ranges　from　723　K　to　973　K,　GHSV　is　720　h-1,　water/ethanol　molar　ratio　are　6:1　and　4:1,　respectively.　However,　as　the　Cu49Zn21Al18Zr12　catalyst　gains　a　relatively　higher　productivity　over　873　K　and　lower　cost　than　Pt/CZO/Al2O3　catalyst,　steam　reforming　of　ethanol　over　Cu49Zn21Al18Zr12　catalyst　may　become　a　promising　and　practical　way　for　producing　hydrogen　on　vehicles.