A photocurable silicone composition comprising: (A) an organopolysiloxane represented by the following average composition formula: R 1 a R 2 bSiO (4-a-b)/2 wherein, R 1 is a C 2-12 alkenyl group; R 2 is a C 1-12 alkyl group, a C 6-12 aryl group, or a C 7-12 aralkyl group; provided that at least one R 2 in a molecule is the aryl group or the aralkyl group; and "a" and "b" are positive numbers satisfying: 1≤a+b≤2.5 and 0.001≤a/(a+b)≤0.2; (B) a polysiloxane block copolymer comprising: (i) a polysiloxane block represented by the general formula: (R 3 2 SiO) n , wherein each R 3 is independently a C 1-12 alkyl group, a C 6-12 aryl group, or a C 7-12 aralkyl group; and "n" is a positive number of at least about 5; and (ii) an organo block containing at least three sulfur atoms and free of silicon atom in a chemical structure thereof, wherein the polysiloxane block (i) is bonded to the organo block (ii) via a linkage represented by the general formula: (Si)-R 4 -(S), wherein Si is an atom in a chemical structure of the polysiloxane block (i); S is an atom in a chemical structure of the organo block (ii); and R 4 is a C 2-6 alkylene group, and wherein the polysiloxane block copolymer has at least two thiol (HS-) groups in a molecule, in an amount such that the thiol groups in component (B) is in a range of from 0.2 to 2.0 moles per 1 mole of the total alkenyl groups in component (A); (C) a photoinitiator, in an amount of from 0.01 to 5 parts by mass of per 100 parts by mass of a total mass of components (A) and (B); and (D) an inorganic filler, in an amount of from about 0.01 to about 40 parts by mass per 100 parts by mass of a total mass of components (A) and (B). (A) an organopolysiloxane represented by the following average composition formula: R 1 a R 2 bSiO (4-a-b)/2 wherein, R 1 is a C 2-12 alkenyl group; R 2 is a C 1-12 alkyl group, a C 6-12 aryl group, or a C 7-12 aralkyl group; provided that at least one R 2 in a molecule is the aryl group or the aralkyl group; and "a" and "b" are positive numbers satisfying: 1≤a+b≤2.5 and 0.001≤a/(a+b)≤0.2; (B) a polysiloxane block copolymer comprising: (i) a polysiloxane block represented by the general formula: (R 3 2 SiO) n , wherein each R 3 is independently a C 1-12 alkyl group, a C 6-12 aryl group, or a C 7-12 aralkyl group; and "n" is a positive number of at least about 5; and (ii) an organo block containing at least three sulfur atoms and free of silicon atom in a chemical structure thereof, wherein the polysiloxane block (i) is bonded to the organo block (ii) via a linkage represented by the general formula: (Si)-R 4 -(S), wherein Si is an atom in a chemical structure of the polysiloxane block (i); S is an atom in a chemical structure of the organo block (ii); and R 4 is a C 2-6 alkylene group, and wherein the polysiloxane block copolymer has at least two thiol (HS-) groups in a molecule, in an amount such that the thiol groups in component (B) is in a range of from 0.2 to 2.0 moles per 1 mole of the total alkenyl groups in component (A); (i) a polysiloxane block represented by the general formula: (R 3 2 SiO) n , wherein each R 3 is independently a C 1-12 alkyl group, a C 6-12 aryl group, or a C 7-12 aralkyl group; and "n" is a positive number of at least about 5; and (ii) an organo block containing at least three sulfur atoms and free of silicon atom in a chemical structure thereof, (C) a photoinitiator, in an amount of from 0.01 to 5 parts by mass of per 100 parts by mass of a total mass of components (A) and (B); and (D) an inorganic filler, in an amount of from about 0.01 to about 40 parts by mass per 100 parts by mass of a total mass of components (A) and (B). <EOS>