<p>Disclosed is a transdermal preparation which has the following basic properties required for a transdermal preparation: a permeation promoter can be added to the transdermal preparation in a large quantity without reducing the coagulation ability of an adhesive agent contained in the transdermal preparation; the bioavailability of a pharmaceutically active ingredient contained in the transdermal preparation can be improved; the amount of an adhesive agent remaining on the skin or the sticky feeling on the skin can be reduced; and others. Specifically disclosed is a transdermal preparation comprising a support and an adhesive layer comprising an adhesive composition and arranged on the support. In the transdermal preparation, the adhesive composition comprises: an acrylic adhesive agent mainly composed of a resin that is produced by polymerizing a monomer comprising an acrylic acid ester and/or a methacrylic acid ester each having no carboxyl group in the molecule or a mixture of the monomer; a basic and pharmaceutically active ingredient; silica particles having an average particle diameter of 5 µm or less; and a polyhydric alcohol fatty acid ester, wherein the polyhydric alcohol fatty acid ester is contained in an amount of 15 to 40 mass% relative to the total mass of the adhesive composition.</p>