The　Organobentonites　were　synthesized　by　means　of　the　ionexchange　reaction　of　Na+　between　tetramethylammonium　chloride　and　tetrabutylammonium　chloride　quaternary　ammonium　salts,　and　sodium　base　bentonites.　The　authors　used　FTIR,　X-ray　diffraction　diagram　and　DSC　thermograms　to　characterize　the　structure　of　the　modified　bentonites,　and　discussed　the　effect　of　different　quaternary　ammonium　salt　on　the　properties　of　organobentonites.　The　results　showed　that　ions　of　the　surfactants　had　entered　into　the　chip　layer　of　the　bentonites,　changed　the　hydrophilic　environment　of　the　chip　layer　into　a　hydrophobic　environment,　increased　the　distance　among　the　chip　layers,　and　improved　the　compatibility　between　montmorillonite　and　the　organic　phases.　All　of　these　have　laid　a　base　for　the　preparation　of　nanometer　composite　material　of　high　polymer/bentonite.