The invention provides a PPS resin composition having excellent heat resistance and excellent electrical properties without damaging excellent physical properties including mechanical properties and low gas generation which PPS intrinsically has. There is provided a resin composition comprising (a) a polyphenylene sulfide resin and (b) one or more copolymers selected among a tetrafluoroethylene/hexafluoropropylene copolymer, an ethylene/tetrafluoroethylene copolymer and a tetrafluoroethylene/perfluoro(alkyl vinyl ether) copolymer. In the resin composition, (a) the polyphenylene sulfide resin forms a continuous phase, (b) one copolymer selected among the above components forms primary dispersed phases, and the primary dispersed phase includes secondary dispersed phases formed by a component different from the component of the primary dispersed phase.