In this work, the surface properties of poly(ether imide) (Ultem) were analyzed by inverse gas chromatography. Four n-alkanes (n-C7, n-C8, n-C9 and n-C10) were chosen as nonpolar probes to characterize the surface dispersive free energy at different temperatures. The retentions of tetrahydrofurane, dichloromethane, chloroform, ethyl acetate and diethyl ether on Ultem were measured in the temperature range from 303.2 K to 328.2 K by inverse gas chromatography. The dispersive component of the surface free energy, gamma(D)(S) of studied adsorbent surface was estimated using retention times of different nonpolar organics in the infinite dilution region. Thermodynamic parameters of adsorption (free energy, Delta G(A)(S), enthalpy, Delta H-A(S) and entrophy, Delta S-A(S)), dispersive components of the acid, K-A and base, K-D constants for the Ultem were calculated. The results mean that Ultem was a strong basic polymer.