Impregnated　Y2O3　Doped　Tungsten　Matrix　Scandate　Cathode　was　prepared　by　impregnating　Y2O3-W　matrix　with　barium-aluminum-scandate.　The　zero　current　density　J(0)　of　the　cathode　at　900　degrees　C-b　has　reached　14.63A/cm(2)　and　secondary　emission　yield　delta　is　3.51　after　being　optimally　activated,　both　higher　than　the　emission　performances　of　Ba-W　dispenser　cathode.　Auger　electron　spectroscopy　result　indicates　that　Sc,　Ba　and　O　diffuses　from　the　interior　porous　body　to　surface　simultaneously　to　form　a　＂Ba-Sc-O＂　active　substance　layer,　which　lowers　the　work　function　of　the　cathode,　and　the　increase　of　Y2O3　content　will　contribute　to　the　formation　of　n-type　semiconductor,　which　enhances　the　electric　conductivity　of　the　cathode,　thus　the　emission　performance　of　the　cathode　has　been　improved.