A series of samples were prepared by treating natural zeolite from Kampo area with HCl and NaOH. And, the adsorption characteristics of some liquid samples were investigated by the Diamond-Kinter method. The adsorption amount of all liquid investigated was more effective in acid treatment than in alkali treatment. In the case of n-, iso-C3H7OH, thed adsorption amount of n-form which has smaller molecular size was larger. Similar tenedncy was observed in n-, iso-C4H9OH, but the amount was lower than n-, iso-C3H7OH. In CHCl3 and CCl4, that of CHCl, which is smaller molecular size and has polarity, was far lager. From the view of the molecular size, adsorption amount of C6H5CH3 and p-C6H4(CH3)2 showed the characteristics of surface activity rather than chemical treatment.