In　this　paper,　we　propose　a　homomorphic　encryption　scheme,　which　is　with　an　innovative　property　to　build　a　robust　operation　security　of　sharing　data-putting-out　between　user,　owner　and　open　agriculture　cloud　service　provider　while　not　revealing　secret　information　about　the　operated　data　and　privacy　of　the　involved　roles.　The　scheme　takes　root　in　Vector　Operation　and　Random　Oracle　Machine.　It　supports　cipher-text　fully-homomorphic　operation,　which　makes　it　possible　to　build　a　secure　data-trust　deployed　on　the　platform　of　cloud　computing.　Theoretical　analysis　proves　that　the　algorithm　could　safeguard　information　security　under　IND-CCA.　Experiment　results　and　comprehensive　estimation　show　that　it　is　provided　with　a　more　favorable　speed　of　homomorphic　encryption　operation　and　manifests　a　more　advantageous　macro　performance　in　parallel　with　existent　ones.　1553-9105/Copyright　©　2013　Binary　Information　Press.