The two-phase base-catalyzed transesterification of vegetable oils with short chain alcohols is common in the production of biodiesel. The reactants (vegetable oil and ethanol) are partially soluble, and this phase behavior can significantly impact the reaction process. To better understand this phase behavior, the liquid-liquid equilibrium data for pseudobinary systems containing vegetable oils (soybean oil, sunflower oil, rice bran oil, cottonseed oil, palm olein, and palm oil) + anhydrous ethanol in the range from (298.15 to 333.15) K were determined experimentally. The mutual solubility increased as the temperature rose in all the systems examined. The equilibrium data were correlated with the NRTL model using temperature-dependent parameters which represented satisfactorily the experimental results.