The　structures　and　electronic　properties　of　bimetallic　oxide　CrW2O9　clusters　supported　on　the　perfect　and　defective　MgO(001)　surfaces　with　three　different　color　centers,　F-S(0),　F-S(+),　and　F-S(2+)　centers,　respectively,　have　been　investigated　by　density　functional　theory　calculations.　Our　results　show　that　the　configurations,　adsorption　energies,　charge　transfers,　and　bonding　modes　of　dispersed　CrW2O9　clusters　are　sensitive　to　the　charge　states　of　the　FS　centers.　Compared　with　the　gas-phase　configuration,　the　CrW2O9　clusters　supported　on　the　defective　surfaces　are　distorted　dramatically,　which　exhibit　different　chain　structures.　On　the　perfect　MgO　surface,　the　depositions　of　clusters　do　not　involve　obvious　charge　transfer,　while　the　situation　is　quite　different　on　the　defective　MgO(001)　surfaces　in　which　significant　electron　transfer　occurs　from　the　surface　to　the　cluster.　Interestingly,　this　effect　becomes　more　remarkable　for　electron-rich　oxygen　vacancies　(F-S(0)　center)　than　that　for　electron-poor　oxygen　vacancies　(F-S(+)　and　F-S(2+)　centers).　Furthermore,　our　work　reveals　a　progressive　Bronsted　acid　sites　where　spin　density　preferentially　localized　around　the　Cr　atoms　not　the　W　atoms　for　all　kinds　of　FS-centers,　indicating　the　better　catalytic　activities　can　be　expected　for　CrW2O9　cluster　on　defective　MgO(001)　surfaces　with　respect　to　the　W3O9　cluster.　Published　by　AIP　Publishing.