Disclosed is a cosmetic composition containing, as an active ingredient, an ester oil obtained by the bonding and esterification of amyl alcohol or an isomer thereof and a fatty acid derived from a natural vegetable oil such as olive oil or coconut oil. The ester oil increases the viscosity and imparts stability to cosmetics while also having a far better moisturizing ability and a lighter feeling in use than silicone oil, and the invention therefore allows a naturally derived ester oil, which is relatively friendly to the human body, to be used as a fundamental base component of a cosmetic composition, in complete or partial substitution for silicone oil which has been used on account of the shortcomings of existing synthetic ester oils.
