Al- and Al/Ni- pillared clays were prepared by intercalation of Na-montmorillonite separated from Jelsovy Potok bentonite (Slovakia). Adsorption and desorption isotherms of water (at 291 K) and argon (at 77 K) on Na- and pillared montmorillonites were determined. Na-montmorillonite adsorbed water gradually with increasing relative vapour pressure, while pillared forms adsorbed water more rapidly at low p/p_s ratio, because of a bigger micropore volume in comparison with the Na-form. The large portion of adsorbed water under the high relative pressure corresponds with the swelling ability of Na-montmorillonite. Lower adsorption of pillared montmorillonites in this region is due to partial loss of swelling ability. Pillared montmorillonites exhibited extreme type-I Langmuir isotherms for argon and sorption of water vapour produced the isotherms of unusual shape. This could be the consequence of the pore size distribution and hydrophobic nature of the pillared forms. Though the adsorbed amount of argon on pillared montmorillonites was bigger than on Na-montmorillonite, the differences between adsorption and desorption values at the same p/p_s ratios were minor for all three samples.