Thermodynamic functions characterizing adsorption of binary mixtures in microporous materials are studied by way of the analytical results for inhomogeneous square-well mixtures in one-dimension. The calculations were done for two bulk mixtures : an ideal one and an athermal one. The results show the influence of different adsorbate-wall interactions, pore size, and dispersity in pore sizes on adsorption excess isotherms and thermodynamic functions (Gibbs energy, enthalpy, and entropy of immersion), especially for liquid mixture adsorption. The porous materials are characterized by pore size distributions that range from monodisperse to broadly polydisperse. Additionally, density profiles and Henry’s law constants are presented to illustrate the various effects that occur.