The vapor-liquid equilibrium (VLE) data of different mass fractions of the mixture (ethyl fluoride (HFC-161) + alkylbenzene (AB) lubricant oil) at a temperature range from (278.15 to 348.15) K were measured by single-phase cycle method, and the solubility and miscibility for the mixture (HFC-161 + AB lubricant oil) were analyzed in this paper. The experimental results showed that there was no stratification, no sediment generation, and no color change during the whole experiment for the mixture (HFC-161 + AB lubricant oil). The vapor pressure decreased with the increase of oil concentration. The experimental results were correlated by the nonrandom two-liquid (NRTL) equation. The parameters of the NRTL equation were regressed. From the correlated results, the average relative pressure deviation was 1.4 %, and the maximum relative pressure deviation was 4.2 %. Meanwhile, the results were compared with those of the HFC-161 + polyol ester (POE) lubricant oil mixture in the temperature range of (278.15 to 328.15) K. For a given HFC-161 mass fraction and temperature, HFC-161 is more soluble in POE lubricant oil than in AB lubricant oil. In this work, AB lubricant oil may be a better choice for HFC-161 than POE lubricant oil to some extent.