The total vapor pressure of liquid mixtures of xenon and cyclopropane has been measured at 161.39 K (the triple-point of xenon) and at 182.33 K (the triple-point of dinitrogen oxide), as a function of composition. At 182.33 K the liquid densities were also measured. The mixtures show positive deviations from Raoult's law. Both the excess molar Gibbs energy (G m E) and the excess molar volume (V m E) were calculated from the experimental data. For the equimolar mixture, G m E) 90.6 J mol -1 at 161.39 K, G m E) 124.1 J mol -1 at 182.33 K, and V m E) -0.758 cm 3 mol -1 at 182.33 K. The excess molar enthalpy (H m E) could be estimated from the temperature dependence of G m E and found to be -168 J mol -1 . The results were interpreted using the 1cLJ perturbation theory of Fisher et al.