Four vegetable oils are converted into polyoleate esters, with evaluation of their physico-chemical properties as synthetic lubricants. Castor oil, linseed oil, sunflower oil, and jatropha oil were converted into polyols via epoxidation and hydrolysis. Esterification of these polyols with excess oleic acid gave the polyoleate esters 1, 2, 3, and 4, respectively. The results of physico-chemical determinations show that these esters are promising as synthetic lubricants. Esterification of castor oil itself with oleic acid gave the ester 5, which showed poor thermal and oxidative stabilities.