The invention relates to a process for preparing polyoxyalkylene polyester polyols with calculated OH numbers of 320 mg (KOH)/g to 530 mg (KOH)/g by reacting a starter compound, which contains alcoholic hydroxy groups and/or amine protons, and a fatty acid ester containing an alkylene oxide. The invention further relates to polyoxyalkylene polyester polyols resulting from the method and to a preparation method for polyurethanes by reaction of the polyoxyalkylene polyester polyols according to the invention with polyisocyanates.