Three organobentonites were synthesized by placing cation surfactants such as octadecyltrimethylammonium bromide (OTMAD ), cetyltrimethylammonium bromide (CTMAB) and dodecyltrimethylammonium bromide(DTMAB) on bentonite. The properties for organobentonites to adsorb phenol, p-nitrophenol, aniline, nitrobenzene and 1-naphthylamine in water were investigated in detail. The mechanism that organic compounds were adsorbed by organobentonites was studied. The removal rates for organobentonites to treat organic compounds from water were associated with the properties of organic compounds, the ammount of cation surfactants exchanged on the bentonite and the length of alkyl chain of the cation surfactant.