In a plaster for external use for transdermal absorption in which an adhesive layer is laminated on a plastic backing, the adhesive layer contains a styrene-isoprene-styrene block copolymer (SIS), a tackifying resin and a softener which are essential ingredients, and further contains flurbiprofen blended as an active ingredient. The present plaster for external use is a flurbiprofen containing plaster for external use enabling long-term stable release of contained flurbiprofen, and having excellent stability and very high drug releasing property.