Isothermal vapor liquid equilibrium (VLE) data for the ternary mixture of 1,1,1,2-tetrafluoroethane (HFC-134a) + 2,3,3,3-tetrafluoroprop-1-ene (HFO-1234yf) + dimethyl ether (DME) were measured at temperatures from 253.15 K to 323.15 K using a recirculation apparatus. The experimental data were correlated by the PR (Peng-Robinson) equation of state with the LCVM (linear combination of Vidal and Michelsen) mixing rule and the NRTL (nonrandom two liquid) model. The average absolute vapor composition deviations are 0.007 (for HFC-134a) and 0.012 (for HFO-1234yf), and the largest absolute deviation of the vapor compositions are 0.022 (for HFC-134a) and 0.031 (for HFO-1234yf; the average relative pressure deviation is within 1.2 % and its largest relative pressure deviation is 3.7 %. The correlation results are in good agreement with the experiment results. With the regressed parameters obtained by the ternary mixture (HFC-134a + HFO-1234yf + DME), the VLE of two binary mixtures (HFC-134a + HFO-1234yf and HFC-134a + DME) were predicted by the PR + LCVM + NRTL model. The predicted results were compared with the experimental data of other researchers. The results showed that the regressed parameters obtained by the ternary mixture (HFC-134a + HFO-1234yf + DME) in this work could be used to predict VLE behavior of the binary mixtures. The results also indicated that there is no azeotrope in the ternary mixture.