An addition curing silicone composition for release paper or film, comprising 100 parts by weight of organopolysiloxane containing at least two alkenyl groups in the molecule and having a viscosity of at least 0.04 Pa-s at 25°C, 0.1 to 10 parts by weight of adhesion promoter which is an organopolysiloxane compound of linear or branched siloxane structure having the general formula or and having a viscosity of less than 0.04 Pa-s at 25°C: wherein R 1 is an alkenyl-containing substituent group of 2 to 10 carbon atoms, R 2 is substituted or unsubstituted monovalent hydrocarbon group of 1 to 10 carbon atoms, Y is a group of the following formula: wherein R 1 and R 2 are as defined above, Y 1 is a group of the following formula: wherein R 1 and R 2 are as defined above, a2, b2, ay, and by are each an integer of 0 to 48, c2 and cy are each an integer of 0 to 30 and d2 and dy are each an integer of 0 to 20; formulae, and each denote a random structure and include at least one structure in which two siloxane units in which the alkenyl-containing substituent group R 1 is bonded to silicon atom are linked directly or via up to 3 intervening siloxane units in which R 1 is not bonded to silicon atom; wherein R 1 and R 2 are as defined above, Z is a group of the following formula: wherein R 1 and R 2 are as defined above, Z 1 is a group of the following formula: wherein R 1 and R 2 are as defined above, a2, b2, ay, and by are each an integer of 0 to 48, c2 and cy are each an integer of 0 to 30 and d2 and dy are each an integer of 0 to 20, formulae, and each denote a random structure and include at least one structure in which two siloxane units in which the alkenyl-containing substituent group R 1 is bonded to silicon atom are linked directly or via up to 3 intervening siloxane units in which R 1 is not bonded to silicon atom; 0.1 to 20 parts by weight of an organohydrogenpolysiloxane containing at least three silicon-bonded hydrogen atoms in the molecule, a catalytic amount of a platinum group metal base catalyst, and optionally, an organic solvent. 100 parts by weight of organopolysiloxane containing at least two alkenyl groups in the molecule and having a viscosity of at least 0.04 Pa-s at 25°C, 0.1 to 10 parts by weight of adhesion promoter which is an organopolysiloxane compound of linear or branched siloxane structure having the general formula or and having a viscosity of less than 0.04 Pa-s at 25°C: wherein R 1 is an alkenyl-containing substituent group of 2 to 10 carbon atoms, R 2 is substituted or unsubstituted monovalent hydrocarbon group of 1 to 10 carbon atoms, Y is a group of the following formula: wherein R 1 and R 2 are as defined above, Y 1 is a group of the following formula: wherein R 1 and R 2 are as defined above, a2, b2, ay, and by are each an integer of 0 to 48, c2 and cy are each an integer of 0 to 30 and d2 and dy are each an integer of 0 to 20; formulae, and each denote a random structure and include at least one structure in which two siloxane units in which the alkenyl-containing substituent group R 1 is bonded to silicon atom are linked directly or via up to 3 intervening siloxane units in which R 1 is not bonded to silicon atom; wherein R 1 and R 2 are as defined above, Z is a group of the following formula: wherein R 1 and R 2 are as defined above, Z 1 is a group of the following formula: wherein R 1 and R 2 are as defined above, a2, b2, ay, and by are each an integer of 0 to 48, c2 and cy are each an integer of 0 to 30 and d2 and dy are each an integer of 0 to 20, formulae, and each denote a random structure and include at least one structure in which two siloxane units in which the alkenyl-containing substituent group R 1 is bonded to silicon atom are linked directly or via up to 3 intervening siloxane units in which R 1 is not bonded to silicon atom; wherein R 1 and R 2 are as defined above, a2, b2, ay, and by are each an integer of 0 to 48, c2 and cy are each an integer of 0 to 30 and d2 and dy are each an integer of 0 to 20; formulae, and each denote a random structure and include at least one structure in which two siloxane units in which the alkenyl-containing substituent group R 1 is bonded to silicon atom are linked directly or via up to 3 intervening siloxane units in which R 1 is not bonded to silicon atom; wherein R 1 and R 2 are as defined above, Z is a group of the following formula: wherein R 1 and R 2 are as defined above, Z 1 is a group of the following formula: wherein R 1 and R 2 are as defined above, a2, b2, ay, and by are each an integer of 0 to 48, c2 and cy are each an integer of 0 to 30 and d2 and dy are each an integer of 0 to 20, formulae, and each denote a random structure and include at least one structure in which two siloxane units in which the alkenyl-containing substituent group R 1 is bonded to silicon atom are linked directly or via up to 3 intervening siloxane units in which R 1 is not bonded to silicon atom; wherein R 1 and R 2 are as defined above, a2, b2, ay, and by are each an integer of 0 to 48, c2 and cy are each an integer of 0 to 30 and d2 and dy are each an integer of 0 to 20, formulae, and each denote a random structure and include at least one structure in which two siloxane units in which the alkenyl-containing substituent group R 1 is bonded to silicon atom are linked directly or via up to 3 intervening siloxane units in which R 1 is not bonded to silicon atom; 0.1 to 20 parts by weight of an organohydrogenpolysiloxane containing at least three silicon-bonded hydrogen atoms in the molecule, a catalytic amount of a platinum group metal base catalyst, and optionally, an organic solvent.