An optimization has been performed for the parameters of an Anisotropic United Atoms intermolecular potential for benzene for thermodynamic property prediction using Gibbs Ensemble and NPT Monte Carlo simulations. The optimization procedure is based on the minimization of a dimensionless error criterion incorporating various thermodynamic data (saturation pressure, vaporization enthalpy, and liquid density) at ambient conditions and at 450 K. A comprehensive comparison of the new model is given with six intermolecular potentials taken from the literature. Overall, thermodynamic property estimations of our optimized model are in very good agreement with experimental data. The new model also provides a good representation of the liquid structure, as revealed by the carbon-carbon radial distribution function.