A resin composition suitable for manufacturing an electrical insulative resin film for a printed wiring board is composed of 80 to 99.5 mass % of a first graft copolymer (a) and 0.5 to 20 mass % of a second graft copolymer (b). In the first graft copolymer (a), 15 to 40 parts by mass of an aromatic vinyl monomer are grafted to 60 to 85 parts by mass of a random or block copolymer composed of monomer units selected from nonpolar alpha-olefin monomers and nonpolar conjugated diene monomers. In the second graft copolymer (b), 5 to 30 parts by mass of an aromatic vinyl monomer are grafted to 70 to 95 parts by mass of a random or block copolymer composed of 60 to 90 mass % of a monomer unit, which is selected from nonpolar alpha-olefin monomers and nonpolar conjugated diene monomers, and 10 to40 mass % of an aromatic vinyl monomer unit.