Ethanol with alkyl esters (biodiesel) mixtures as co-solvent was successfully applied to extract oil from soybean flakes. The effect of operating temperature, solvent to soybean mass ratio and mass of biodiesel in ethanol at different concentrations was evaluated on the kinetics and the extraction yield. High extraction rates and overall extraction yield were obtained at higher temperatures and for all solvents mixtures evaluated. At lower temperatures, the effect of biodiesel as a co-solvent was more pronounced. Mixtures of (ethanol + biodiesel) showed, in general, a greater ability to extract the solute when compared to ethanol as the solvent. The highest extraction conditions were those using absolute ethanol at 55 ◦C, with or without biodiesel, and also those using a mixture of (20% of biodiesel added to hydrated ethanol (96%), in mass) as solvent.