The　La,　Y-Mo　composite　oxide　powder　was　successfully　prepared　by　the　Sol-Gel　method.　The　technique　terms　are　as　follows:　the　pH　value　of　the　precursor　solution　is　1;　the　decomposition　temperature　is　550　degreesC.　The　reduction　temperature　of　the　first　step　is　500degreesC　and　of　the　second　900degreesC.　The　composition,　microgram　and　granularity　of　the　powder　are　studied　by　the　XRD,SEM,　etc.　The　results　show　that　the　molybdenum　appear　after　the　reduction　at　500degreesC　and　the　rare　earth　elements　consist　in　the　structure　of　RE-O-Mo.　After　the　second　reduction,　the　rare　earth　elements　consist　with　the　form　of　the　rare　earth　oxide.　The　results　from　the　infrared　spectrum　(FT-IR)　show　that　the　bond　of　the　Mo　=　O　is　weakened　due　to　the　bond　of　the　RE-O-Mo,　leading　to　the　increase　of　the　reduction　properties　of　the　RE-Mo　composite　oxide　powders.　The　results　also　show　that　the　granularity　of　the　RE-Mo　powder　is　about　70　nm.