[Objective] To provide a pressure-sensitive adhesive agent for skin containing a pressure-sensitive adhesive agent for skin that has favorable shape retention properties and skin-follow up properties without being adversely affected by moisture from excrement or the like even when adhered to the skin over a long period of time and yet leaves no adhesive residue after separation and a pressure-sensitive adhesive sheet for skin contains a base material and a layer of the pressure-sensitive adhesive agent for skin. [Means to Achieve Objectives] A pressure-sensitive adhesive agent for skin contains 2 to 35% by weight of a thermoplastic elastomer, 25 to 60% by weight of a hydrophilic polymer compound, 16 to 40% by weight of a softener, and 0.01 to 4.8% by weight of a physiologically active agent; and has a water absorption 3 hours after of 55 to 240% and a water absorption 24 hours after of 240 to 450%. A pressure-sensitive adhesive sheet for skin contains a base material and a layer of a pressure-sensitive adhesive agent for skin that contains 2 to 35% by weight of a thermoplastic elastomer, 25 to 60% by weight of a hydrophilic polymer compound, 16 to 40% by weight of a softener, and 0.01 to 4.8% by weight of a physiologically active agent and is formed on one side of the base material; and has a water absorption 3 hours after of 55 to 240% and a water absorption 24 hours after of 240 to 450%.