Abstract: The curable resin composition of the present technology includes: (A) a straight-chain organopolysiloxane having at least two silicon-bonded hydrogen atoms and at least one aryl group in one molecule and having an average degree of polymerization of greater than 10; (B) a branched-chain organopolysiloxane having at least three alkenyl groups and at least one aryl group in one molecule; and (C) a hydrosilylation reaction catalyst; wherein a proportion of diphenylsiloxane units relative to an amount of all siloxane units is 10 mol % or greater, and the all siloxane units containing siloxane units derived from the straight-chain organopolysiloxane (A) and the branched-chain organopolysiloxane (B).