Disclosed is a percutaneous absorption preparation which enables the stable administration of an antidementia drug over a long period of time. More particularly, the percutaneous absorption preparation of the antidementia drug which is used as a plaster on skin comprises at least an adherent layer, an intermediate membrane, and a drug reservoir layer sequentially from the side which is plastered on skin, wherein the drug reservoir layer comprises at least an antidementia drug, an aminated polymer, a polyhydric alcohol, and one or more carboxylic acid esters, the intermediate membrane enables the controlled permeation of the antidementia drug into the side of skin, the adherent layer enables the plastering of the percutaneous absorption preparation on skin, and is permeable to the antidementia drug.