Mixtures of novolac resin and olive stone biomass in proportions 20 : 80 (w : w) are cured, pyrolyzed up to 1000 degrees C (material C20), and activated with steam (material C20a). The adsorption properties of these materials and a commercial activated carbon (CC) are investigated based on the adsorption of nitrogen and pentane. The adsorption capacity, the surface area determined by the BET and DRK equation, and the pore volume determined as micropore volume by the DR equation, and as cumulative pore volume related to the Kelvin equation, for the materials follow the order C20a, CC > C20. The DR equation can be applied for the adsorption of nitrogen on the materials examined in the region of PIPo = 0.005 up to 0.3 that exceeds in both sides the common range for the applicability of the DR equation. The activated materials C20a and CC are mainly microporous and reveal the type I isotherms of the Brunauer classification for nitrogen adsorption. The only pyrolyzed material, C20, contains both micropores and mesopores and reveals characteristics of both types I and II. The number of layers for C20a and CC is lower than 2 and for C20 is more than 2.