Experimental bubble point isopleths for the binary system carbon dioxide + 1,2-epoxycyclohexane have been determined for mole fractions from (10 to 50) % CO2 and temperatures from (354 to 424) K. Vapor pressures and liquid densities of pure 1,2-epoxycyclohexane have been measured from (361 to 474) K and from (278 to 363) K, respectively. Using the Peng-Robinson equation of state and van der Waals one-fluid mixing rules, a good description of the phase behavior of both the vapor pressure and the bubble point data has been obtained. The binary interaction parameter k(ij) has been found to be temperature-dependent.