It　is　of　great　significance　to　separate　hazardous　methyl　tert-butyl　ether　(MTBE)　from　water　in　terms　of　environmental　protection　and　human　health.　In　the　present　work,　alpha-Al2O3-suppotred　silica　membranes　were　prepared　by　the　sol-gel　and　dip-coating　technique.　Two　fluorinated　alkylsilanes　(1H,1H,2H,2H-perfluorooctyltriethoxysilane　(PFOTES)　and　trifluoropropyltriethoxysilane　(TFPTES))　and　two　non-fluorinated　alkylsilanes　(octyltriethoxysilane　(OTES)　and　propyltriethoxysilane　(PTES))　were　adopted　to　silylate　the　silica　membrane　by　the　post-grafting　method　which　is　used　for　the　separation　of　MTBE　from　water　by　pervaporation.　The　results　show　that　silylation　enhances　the　hydrophobicity　of　silica　membranes.　The　silylated　silica　membranes　are　selective　towards　MTBE,　and　the　MTBE/water　separation　factor　varies　with　grafting　agents　in　the　order:　PFOTES　＞　TFPTES　＞　OTES　＞　PTES.　Membranes　silylated　with　fluorinated　carbon　chains　seem　to　be　more　selective　towards　MTBE　than　those　with　non-fluorinated　carbon　chains.　The　total　flux　is　proportional　to　the　pore　volume　of　silica　membranes,　which　depends　on　grafting　agents　in　the　order:　PTES　＞　PFOTES　＞　OTES　＞　TFPTES.　Considering　both　total　flux　and　selectivity,　the　PFOTES-SiO2　membrane　is　most　effective　in　separation,　with　a　MTBE/water　separation　factor　of　24.6　and　a　total　flux　of　0.35　kg　m(-2)　h(-1)　under　a　MTBE　concentration　of　3.0%　and　a　feed　temperature　of　30　degrees　C.