Provided is a pressure-sensitive adhesive composition that makes it possible to prevent electrification of a non-antistatic protected material during peeling, is reduced in the risk of staining the protected material, and has good removability, and to provide a pressure-sensitive adhesive layer, a pressure-sensitive adhesive sheet. Specifically provided is a pressure-sensitive adhesive composition which comprises: a (meth)acryl-based polymer including, as a main component, a (meth)acryl-based monomer component having an alkyl group of 1 to 14 carbon atoms; an alkali metal salt; and an organopolysiloxane having a polyoxyalkylene side chain, wherein the (meth)acryl-based polymer has an acid value of 1.0 or less, and the total amount of the alkali metal salt and the organopolysiloxane is from 0.15 to 4 parts by weight, based on 100 parts by weight of the (meth)acryl-based polymer.