A new molecular model for ethylene oxide (C2H4O) is developed and optimized using experimental data on vapor pressure. bubble density, and enthalpy of vaporization. This simple molecular model, consisting of three Lennard-Jones sites plus one static point dipole, is used for predicting a wide variety of thermo-physical properties. These are phase equilibria, thermal, caloric, transport properties, and surface tension. The results from the new molecular model are compared to experimental data and to results obtained with ail ethylene oxide model from the literature [Wielopolski and Smith, Mol. Phys. 54 (1985) 467-478]. For all studied properties. the new model gives distinctly improved predictions. (c) 2008 Elsevier B.V. All rights reserved.