Excess molar volumes V-m(E) and excess molar enthalpies H-m(E) were measured as a function of mole fraction at T = 303.15 K and atmospheric pressure for each of the mixtures {1-heptyne, or 1-octyne + tetramethylene sulfone (sulfolane)}. Excess molar volumes were also measured for mixtures of (1-hexyne + sulfolane). The results were compared in an attempt to investigate the interactions between the highly polar sulfolane molecule and the terminal proton of the alkynes. The H-m(E) results were discussed in terms of the NRTL and Wilson models and were predicted from equimolar values of V-m(E) by the Prigogine-Flory-Patterson (PFP) theory with a fi ee volume contribution obtained from Flory's equation of state model. The results were compared with the modified UNIFAC model. The description of H-m(E) by the PFP theory was better than the prediction by the modified UNIFAC.