A solventless silicone pressure-sensitive adhesive composition is provided. The composition includes (A) a polyorganosiloxane with a polymerization degree of 300 to 2,000 and having at least two alkenyl group-containing organic groups, (B) a polyorganohydrosiloxane having at least three silicon-bonded hydrogen atoms, (C) a polydiorganosiloxane having alkenyl groups at both terminals, (D) a polydiorganosiloxane having SiH groups at both terminals, (E) a polyorganosiloxane composed of R23SiO1/2 units and SiO2 units (R2 is a monovalent hydrocarbon group), and (F) a platinum-based catalyst. The composition enables the prevention of problems caused by residual or volatilized organic substances, such as the absorption of ultraviolet radiation or the like, and also enables ready removal of the composition without deforming or damaging the adherend.