Provided is a pressure-sensitive adhesive capable of realizing a pressure-sensitive adhesive layer having satisfactory adhesion performance and a high ink step absorbability. A radiation-curable pressure-sensitive adhesive, which contains a (meth)acryl-based polymer obtained by polymerizing a monomer component containing 30 to 90% by weight of an alkyl(meth)acrylate having an alkyl group of 10 to 22 carbon atoms at an ester end, and having a radically polymerizable functional group containing a carbon-carbon double bond.