An object of the present invention is to provide a percutaneous absorption composition having an improved skin permeability of a basic medicament and an agent for promoting the transdermal absorbability of a basic medicament. The object can be achieved by the use of a percutaneous absorption composition comprising a basic medicament or a salt thereof and sorbic acid and/or its metal salt. The concentration of the sorbate component is preferably from 0.5 mole to 2.5 moles per mole of the basic medicament. Preferably, the composition of the present invention may further comprise an organic basic compound and/or an inorganic basic component.