A　new　kind　of　RE2O3-Mo　cathodes　co-doped　with　Y2O3　and　Lu2O3　were　prepared　by　a　solid-liquid　method　combined　with　the　spark　plasma　sintering　technique.　The　secondary　electron　emission　property　and　secondary　emission　mechanism　of　the　cathode　have　been　studied.　The　results　show　that　Y2O3-Lu2O3　co-doped　Mo　cathode　exhibits　better　secondary　emission　property　than　single　Y2O3　doped　molybdenum　cathode,　and　the　maximum　secondary　emission　yield　(delta(max))　can　reach　4.616　after　being　activated　at　900　degrees　C-b.　The　Y2O3-Lu2O3　co-doped　Mo　cathode　has　high　penetration　depth　of　primary　electrons　and　moderate　escape　depth　of　secondary　electrons.　Furthermore,　the　work　function　of　Y2O3-Lu2O3-Mo　cathode　(2.41　eV)　is　lower　than　that　of　Y2O3-Mo　cathode　(3.59　eV).　These　phenomena　are　responsible　for　its　excellent　secondary　emission　property.　(c)　2013　Elsevier　B.V.　All　rights　reserved.