La2O3-Mo,　Y2O3-Mo,　Gd2O3-Mo　and　Ce2O3-Mo　were　prepared　by　liquid-liquid　doping　combined　with　spark　plasma　sintering.　The　microstructure　and　surface　behaviour　of　rare　earth　oxide　of　the　cathode　have　been　studied　by　microscope,　Auger　Electron　Spectroscopy　(AES)　and　X-ray　Photoelectron　Spectroscopy　(XPS)　methods.　Among　these　four　kinds　of　cathode,　Y2O3-Mo　cathode　exhibits　the　best　secondary　emission　property,　i.e..　the　maximum　secondary　emission　yield　could　reach　5.24.　The　penetration　depth　of　primary　electrons　and　escape　depth　of　secondary　electrons　have　been　calculated　and　the　energy　distribution　of　primary　electrons　in　the　cathode　has　been　simulated　by　Monte　Carlo　method.　Y2O3-Mo　cathode　has　the　largest　penetration　depth　and　escape　depth,　which　could　be　attributed　to　the　highest　secondary　electron　emission　yield　of　the　cathode.　(c)　2008　Elsevier　Masson　SAS.　All　rights　reserved.