The problem of the present invention is to provide a composition for enhancing transdermal absorption of a drug, which shows a sufficiently high enhancing effect on transdermal absorption of a drug, particularly, a composition for enhancing transdermal absorption of a drug, which shows a sufficiently high enhancing effect on transdermal absorption of an acidic drug. A composition for enhancing transdermal absorption of a drug, comprising an unsaturated higher alcohol having 12 - 20 carbon atoms and a polyvalent alcohol having 3 - 8 carbon atoms. A composition for enhancing transdermal absorption of a drug, comprising an unsaturated higher alcohol having 12 - 20 carbon atoms, a polyvalent alcohol having 3 - 8 carbon atoms and an organic amine having 2 - 9 carbon atoms.
