Abstract In this work, we apply an equation of state based on statistical-mechanical perturbation theory to liquid mixtures. Three temperature-dependent quantities are needed to use the equation of state (EOS): the second virial coefficient, B( T), effective van der Waals covolume, b( T), and a scaling factor, α( T). The second virial coefficients are calculated from a correlation that uses the heat of vaporization (e.g. Trouton's rule), ΔH vap, and the density at the triple point, ϱ tp. α( T) and b( T) can also be calculated from the second virial coefficient by scaling. Based on the theory, all the three temperature-dependent parameters depend only on the repulsive branch of the potential function, and therefore, by our procedure, can be found from ΔH vap and ϱ tp. It has considerable predicive power, since it only permits the construction of the P- v- T surface from the heat of vaporization plus triple-point density. The equation of state is tested for three-, four-, and five-component liquid mixtures.