The present invention provides an oily base for a cosmetic comprising an ester compound made from a multivalent alcohol and a fatty acid, characterized in that the ester compound is made from dipentaerythritol and at least one fatty acid selected from the group consisting of fatty acids having 5 to 16 carbon atoms and a molar ratio of a dipentaerythritol residue to a fatty acid residue having 5 to 16 carbon atoms in the ester compound is 1.0:3.0 to 1.0:6.0. The aforesaid oily base for a cosmetic has proper oily feeling with moistness, no uncomfortable sticky feeling, excellent safety to the skin and adhesion to the skin, excellent gloss-holding ability after application to the skin, and excellent compatibility with various oil agents. In addition, upon blending the ester compound in various cosmetics, the cosmetics also have proper emollient property.