The purpose of the present invention is to provide a heat-curable silicone resin composition that has excellent heat curing properties and contains a lanthanoid compound. The heat-curable silicone resin composition contains an organo polysiloxane (A) with a silanol group, a silane compound (B) with an alkoxysilyl group, a lanthanoid compound (C), and a zinc compound (D). The amount of silane compound (B) is 0.5-2,000 parts by mass per 100 parts by mass of the organo polysiloxane (A); the amount of the lanthanoid compound (C) is 0.0001-1 parts by mass per 100 parts by mass total of the organo polysiloxane (A) and the silane compound (B); and the amount of the zinc compound (D) is 0.01-5 parts by mass per 100 parts by mass total of the organo polysiloxane (A) and the silane compound (B).