Addition-curable organopolysiloxane resin composition comprising an organopolysiloxane resin that contains at least alkenyl, hydroxyl, and phenyl directly bonded to silicon of which at least 30 mole% is phenyl; an organohydrogenoligosiloxane or organohydrogenpolysiloxane that contains at least phenyl directly bonded to silicon of which at least 20 mole% is phenyl; and an addition reaction-curing catalyst.
