Scandia　and　rhenium　doped　tungsten　powders　have　been　prepared　by　solid-liquid　doping　combined　with　two-step　reduction　method.　The　experimental　results　show　that　scandia　distributes　evenly　in　the　doped　tungsten　powder.　Moreover,　the　addition　of　scandia　and　rhenium　could　decrease　the　particle　size　of　tungsten.　By　using　this　kind　of　powder,　scandia　and　rhenium　doped　tungsten　matrix　with　sub-micrometer　sized　tungsten　grains　and　a　uniform　distribution　of　Sc2O3　together　with　high　pore　density　has　been　obtained.　The　emission　property　result　shows　that　high　space　charge　limited　current　density　of　more　than　30　A/cm(2)　at　850　degrees　C　has　been　obtained　for　this　cathode.　This　excellent　emission　capability　results　from　an　active　layer　uniformly　covering　the　sub-micron　structure　framework　of　the　cathodes.　(c)　2007　Elsevier　B.V.　All　rights　reserved.