An object of the present invention is to provide a resin composition which is excellent in light transmittance and impact resistance. The resin composition of the present invention comprises (a) a polyphenylene ether-based resin, (b) a rubber-modified polystyrene-based resin, and (c) a hydrogenated block copolymer; the total 100 parts by mass of the components (a), (b) and (c) include 40-80 parts by mass of (a), a total 20-60 parts by mass of (b) and (c), a mass ratio between (b) and (c) is 20/80-80/20, (b) is a resin obtained by polymerizing a styrenic compound and a compound copolymerizable with the styrenic compound in the presence of a rubbery polymer, and the average particle size of the particles of the rubbery polymer is 2.0 [mu]m or less.