A silicone pressure-sensitive adhesive composition comprising 100 to 40 parts by weight of an organopolysiloxane represented by the average compositional formula and having at least two alkenyl-containing organic groups per molecule, wherein R 1 is each independently a C 1 -C 10 monovalent hydrocarbon group, at least two of R 1 containing a C 2 -C 10 alkenyl-containing organic group, a is an integer of at least 2, b is an integer of at least 1, c is an integer of at least 0, d is an integer of at least 0, and 50 ≤ a+b+c+d ≤ 15,000, 60 to 0 part by weight of a polyorganosiloxane comprising R 2 3 SiO 1/2 units and SiO 4/2 units wherein R 2 is each independently a C 1 -C 10 monovalent hydrocarbon group free of aliphatic unsaturation or a C 2 -C 6 alkenyl group, in a molar ratio R 2 3 SiO 1/2 /SiO 4/2 of 0.5 to 1.0, wherein the total amount of components and is 100 parts by weight, a polyorganohydrogensiloxane represented by the average compositional formula and containing at least three Si-H groups per molecule, in an amount to provide 0.2 to 15 moles of Si-H groups per mole of alkenyl groups in components and, R 3 e H f SiO (4-e-f)/2 wherein R 3 is each independently a substituted or unsubstituted C 1 -C 10 monovalent hydrocarbon group, e and f are numbers in the range: e > 0, f > 0, and 0 < e+f ≤ 3, a platinum group metal base catalyst for curing by promoting hydrosilylation addition between alkenyl groups in components and and Si-H groups in component, in an amount to give 1 to 500 ppm of metal based on the total weight of components to, and 0.01 to 10 parts by weight relative to the total weight of components to of a compound containing at least one recurring unit having the formula and at least one Si-H group per molecule, wherein R 4 to R 11 are each independently hydrogen, halogen, hydroxyl or a C 1 -C 6 monovalent hydrocarbon group, X is selected from divalent organic groups having the formula: wherein R 12 and R 13 are each independently hydrogen, halogen, hydroxyl or a C 1 -C 6 monovalent hydrocarbon group, and g is an integer of at least 1, and Y is each independently a C 1 -C 6 divalent hydrocarbon group which may contain an ether moiety in its structure, the composition further comprising 0.01 to 100 parts by weight relative to the total weight of components to of an organohydrogenpolysiloxane represented by the average compositional formula, exclusive of component, wherein R 14 is each independently a C 1 -C 10 monovalent hydrocarbon group, h is an integer of at least 1, i is an integer of at least 1, j is an integer of at least 1, k and 1 each are an integer of at least 0, and 5 ≤ h+i+j+k+l ≤ 500, wherein component is an organohydrogenpolysiloxane of formula wherein h=1. 100 to 40 parts by weight of an organopolysiloxane represented by the average compositional formula and having at least two alkenyl-containing organic groups per molecule, wherein R 1 is each independently a C 1 -C 10 monovalent hydrocarbon group, at least two of R 1 containing a C 2 -C 10 alkenyl-containing organic group, a is an integer of at least 2, b is an integer of at least 1, c is an integer of at least 0, d is an integer of at least 0, and 50 ≤ a+b+c+d ≤ 15,000, 60 to 0 part by weight of a polyorganosiloxane comprising R 2 3 SiO 1/2 units and SiO 4/2 units wherein R 2 is each independently a C 1 -C 10 monovalent hydrocarbon group free of aliphatic unsaturation or a C 2 -C 6 alkenyl group, in a molar ratio R 2 3 SiO 1/2 /SiO 4/2 of 0.5 to 1.0, wherein the total amount of components and is 100 parts by weight, a polyorganohydrogensiloxane represented by the average compositional formula and containing at least three Si-H groups per molecule, in an amount to provide 0.2 to 15 moles of Si-H groups per mole of alkenyl groups in components and, R 3 e H f SiO (4-e-f)/2 wherein R 3 is each independently a substituted or unsubstituted C 1 -C 10 monovalent hydrocarbon group, e and f are numbers in the range: e > 0, f > 0, and 0 < e+f ≤ 3, a platinum group metal base catalyst for curing by promoting hydrosilylation addition between alkenyl groups in components and and Si-H groups in component, in an amount to give 1 to 500 ppm of metal based on the total weight of components to, and 0.01 to 10 parts by weight relative to the total weight of components to of a compound containing at least one recurring unit having the formula and at least one Si-H group per molecule, wherein R 4 to R 11 are each independently hydrogen, halogen, hydroxyl or a C 1 -C 6 monovalent hydrocarbon group, X is selected from divalent organic groups having the formula: wherein R 12 and R 13 are each independently hydrogen, halogen, hydroxyl or a C 1 -C 6 monovalent hydrocarbon group, and g is an integer of at least 1, and Y is each independently a C 1 -C 6 divalent hydrocarbon group which may contain an ether moiety in its structure, the composition further comprising 0.01 to 100 parts by weight relative to the total weight of components to of an organohydrogenpolysiloxane represented by the average compositional formula, exclusive of component, wherein R 14 is each independently a C 1 -C 10 monovalent hydrocarbon group, h is an integer of at least 1, i is an integer of at least 1, j is an integer of at least 1, k and 1 each are an integer of at least 0, and 5 ≤ h+i+j+k+l ≤ 500, wherein component is an organohydrogenpolysiloxane of formula wherein h=1.