Vapor-liquid equilibria (VLE) of ETBE (Ethyl Tertiary Butyl Ether)+ethanol, ETBE+octane and ethanol+octane binary systems and ETBE+ethanol+octane ternary system were measured at atmospheric pressure by using an improved Othmer-type apparatus. VLE of the binary systems were found to be thermodynamically consistent. The Wilson equation widely adopted in engineering was successfully applied to correlate VLE of the binary systems. Further, VLE of the ternary system can be predicted by using the binary Wilson parameters of the constituent binary systems.