Isothermal vapor-liquid equilibrium data are reported for ethylene + 1,1,2,3,3,3-hexafluoro-1-propene mixtures at six temperatures in the 258.35-307.38 K range, and pressures up to 4.56 MPa. The experimental data were measured using an apparatus based on the "static-analytic" method equipped with a movable ROLSITM capillary sampler for repeatable and reliable equilibrium phase sampling and handling. The isothermal P-x-y data are well correlated with a model comprised of the Peng-Robinson equation of state containing the Mathias-Copeman alpha function, Wong-Sandler mixing rule, and NRTL local composition model. The combined model is termed "PR-MC-WS-NRTL". The studied system does not exhibit azeotropic behavior nor liquid-liquid immiscibility over the range of investigated temperatures. Mixture critical points are calculated from the experimental vapor-liquid equilibrium data via the extended scaling laws and the PR-MC-WS-NRTL model, and are found to be in good agreement with the experimental isothermal phase envelopes. (C) 2013 Elsevier B.V. All rights reserved.