For the binary system dibutyl ether + o-xylene, isothermal and isobaric vapor liquid equilibrium (VLE) data were measured with the static synthetic and the dynamic method. Additionally, excess enthalpy (H(E)) data were determined by means of an isothermal flow calorimeter, and azeotropic data were investigated using a spinning band column. The experimental data from this work were correlated using linear temperature-dependent UNIQUAC interaction parameters.