Provided is a composition with a viscosity in which coating is possible even with a small amount of solvent, has excellent curability, and in which an Si-based pressure-sensitive adhesive (PSA) (e.g., PSA layer) formed by a curing reaction has a low (e.g., 50° C. or lower) glass transition temperature (Tg) despite having high PSA strength and tack, has favorable wettability, and has favorable mechanical strength and elongation; and an application of the same. A low/solvent-free silicone PSA composition comprises: (A) a chain organopolysiloxane having an aliphatic unsaturated carbon-carbon bond-containing group only on a molecular chain end, (B) a straight-chain organohydrogenpolysiloxane having Si—H only on both ends, (C) an organopolysiloxane resin with a weight average molecular weight that is less than 5000, (D) an organopolysiloxane having one or more aliphatic unsaturated carbon-carbon bond-containing groups at locations other than an end and three or more in a molecule, and (E) a hydrosilylation-reaction catalyst.