Organic-inorganic　hybrid　silica　membranes　were　prepared　by　sol-gel　method　with　bridged　silsesquioxane[1,2-bis(triethoxysilyl)　ethane,　BTESE]　and　phenyltriethoxysilane　(PTES)　as　precursors.　The　pore　structure　and　hydrophobic　property　of　the　hybrid　silica　membranes　were　characterized　by　N-2　adsorption,　contact　angle　meter,　TG　and　FTIR.　The　hydrogen　permeation　and　separation　performance　was　also　investigated.　The　results　show　that　the　modified　hybrid　silica　membranes　possess　a　desirable　microporous　structure　with　a　pore　width　centered　at　0.4-0.6　nm.　Such　a　pore　structure　can　be　retained　after　aging　for　30　d　under　a　temperature　of　40　degrees　C　and　a　relative　humidity　of　70%-80%.　The　hybrid　silica　membranes　become　hydrophobic　after　modification,　with　a　water　contact　angle　of　(125　+/-　0.4)　at　a　PTES/BTESE　molar　ratio　of　0.6.　The　transportation　of　hydrogen　in　the　hybrid　silica　membranes　complies　with　the　activated　diffusion　mechanism,　with　a　permeance　of　8.71　x　10(-7)　mol　.　m(-2)　.　Pa-1　.　s(-1)　and　a　H-2/CO2　permselectivity　of　5.53.