The high-pressure vapor-liquid equilibria for supercritical CO2 + citrus oil component (limonene and linalool) + ethanol systems were measured to study an entrainer effect of ethanol. The measured systems were CO2 + limonene + ethanol at 313.2 K and 6.9 MPa; CO2 + linalool + ethanol at 313.2 K and 6.9 MPa and at 333.2 K and 10.0 MPa; and CO2 + limonene + linalool + ethanol at 313.2 K and 6.9 MPa. The experimental apparatus used was based on a circulation-type method for liquid-phase sampling and a flow-type method for vapor-phase sampling. The mole fractions of limonene and linalool in vapor phase are not affected by the addition of ethanol. However, the mole fraction of linalool in the liquid phase decreases with increasing the concentration of ethanol. As a result, the relative volatilities between limonene and linalool increase by factors of 1.2 to 1.5 with the addition of ethanol. The experimental data were correlated by the SRK equation of state with an exponent-type mixing rule. The correlated results are in good agreement with the experimental data.