Isothermal vapor-liquid equilibrium data are presented for the 1,1,2,3,3,3-hexafluoroprop-1-ene and 1,1,2,2,3,3,4,4-octafluorocyclobutane binary system at (292.89, 323.02 and 352.71) K, with pressures ranging from (0.3 to 2.6) MPa. The data were measured using an apparatus based on the static-analytic method, equipped with a single movable rapid online sampler-injector (ROLSI). The expanded uncertainties are estimated at 0.11 K, 4 kPa, 0.010 and 0.007 for the temperature, pressure, and the equilibrium liquid and vapor mole fractions, respectively. The experimental vaporliquid equilibrium data were correlated using the PengRobinson equation of state with the Mathias-Copeman alpha function. The model provides a satisfactory description of the experimental data.