Experimental measurement for the vapor-liquid equilibrium (VLE) of a binary mixture of ethyl fluoride (HFC-161) and polyol ester (POE) lubricant oil is an important task in the practical refrigeration system. In this work, the reliable p-T-x data of HFC-161 + POE (Planetelf ACD 32) are obtained from T = (283.15 to 343.15) K and over a complete range of compositions. Throughout the experiment, there was no stratification and no sediment generation, and the color of mixture liquid remained unchanged. Additionally, the vapor pressure of lubricant oil is negligibly small compared with the one of HFC-161 at the same temperature. Therefore, the mixture vapor is approximated as being pure HFC-161 in this work. The experimental data are correlated by the nonrandom two-liquid (NRTL) model. From the correlated results, the average relative deviation (ARD) of the pressure is 1.94 %, and the maximum relative deviation of the pressure is 5.71 %. The results showed a good agreement with the experimental data.