The silicone-based pressure-sensitive adhesive comprises at least (A) a mixture of (a) a crude rubber-like organopolysiloxane containing one or more alkenyl groups on the average in one molecule and (b) an organopolysiloxane resin substantially consisting of an R31SiO1/2 unit and an SiO4/2 unit or their partial condensation reaction product, (B) an organopolysiloxane containing two or more hydrogen atoms bonded to a silicon atom on the average in one molecule, (C) a phenol-based antioxidant and/or a phenol-modified organosiloxane, (D) an aromatic amine-based antioxidant and/or an aromatic amine-modified organosiloxane and (E) a platinum-based catalyst. To obtain a silicone-based pressure-sensitive adhesive having excellent removability after being exposed in a high temperature.