On condition that OH- / Al3+ molar ration was 2.4, inorgano and inorgano -organo- montmorillonites was synthesized by titrating Na-montmorillonite with hydroxyl aluminum solution. From powder XRD data, it was shown that the interlayer of montmorillonites was increased to 1.9nm and over. The adsorption of nitrobenzene by four modified montmorillonite samples was also studied and the results showed that the adsorbability of inorgano-organomontmorillonites was much better than Na-montmorillonites. The adsorption dynamics follows the laws of Bangham and Langmuir. The relation between adsorbing quantity(qe) and equilibrium concentration (Ce)tallies with the isothermal adsorption equations of Freundlich and Langmuir. The adsorption is presented by heat evolution physisorption and organic partion.