Isobaric vapor-liquid equilibrium (VLE) at SO, 75, and 94 kPa and isothermal interfacial tension (IFT) at 298.15 K for 1-butanol + cyclopentyl methyl ether binary mixture have been experimentally measured in the entire mole fraction range. VLE determinations have been carried out in an all-glass dynamic Guillespie cell over the temperature range from 356 to 386 K, whereas a maximum differential bubble pressure tensiometer is used for atmospheric IFT determinations. According to the experimental results of VLE, the 1-butanol + cyclopentyl methyl ether binary system exhibits a positive deviation from the ideal behavior (or Raoult's law) showing a minimum-boiling azeotropic over the explored pressures. Based on the results, the mole fraction of azeotropy point increases with respect to 1-butanol as pressure and/or temperature. For the case of IFT, a slight positive deviation from the linear behavior is observed, and IFT decreases as the 1-butanol liquid mole fraction increases The reliability of the reported VLE data is confirmed by the point-to-point Van Ness-Fredenlund's consistency thermodynamic evaluation, and also, the VLE data at the three isobaric conditions have been correlated by the Wohl, the NRTL, the Wilson, and the UNIQUAC activity coefficients models. According to the results, the Wilson model provides the best fit. The measurements of the interfacial tension of the mixture are satisfactorily correlated using two parameters of the Myers-Scott equation.