Linear solvation energy relationships, based on application of Kamlet and Taft model, were used to predict the interfacial tension isotherms of l-(2'-hydroxy-5'-methylphenyl)-decane-l-oneoxime in the systems containing octane, toluene and their mixtures as model dilutes. The correlations found permit: (i) to predict the interfacial tension and surface pressure at given concentration of model extractant; (ii) to estimate A and B parameters in Szyszkowski equation and then to predict the whole adsorption isotherms in systems containing various amounts of toluene; (iii) to predict the surface excess for different concentration of extractant in each individual system. The linear solvation energy relationships enable also to formulate semiempirical equations for the interfacial tension, surface pressure and the surface excess isotherms which contain separated effects of extractant concentration and diluent properties.