Experimental data on density and viscosity at 303.15 and 323.15 K are presented for the binary mixtures of sulfolane + benzene, toluene, ethylbenzene, p-xylene, o-xylene, and m-xylene. From these data, excess molar volumes and deviations in viscosity have been calculated. The computed quantities have been fitted to the Redlich-Kister equation to derive the coefficients and estimate the standard error values. The results are discussed in terms of the intermolecular interactions.