Viscosities of the ternary system n-hexane + 1,3-dioxolane + 1-butanol and the binary system n-hexane + 1,3-dioxolane have been measured at atmospheric pressure at 298.15 and 313.15 K. Viscosity deviations for the binary and ternary systems were calculated from experimental data and fitted to Redlich-Kister and Cibulka equations, respectively. The group contribution method proposed by Wu has been used to predict the viscosity of all mixtures.