The objective of the present invention is to provide a rubber-reinforced resin which, when formed into a molded article, can prevent contamination or soiling of an article contacted with the molded article or a device on the periphery of the molded article and is excellent in impact resistance and transparency, and an anti-static resin composition which is excellent in impact resistance and anti-static properties. The present rubber-reinforced resin comprises a rubber-reinforced copolymeric resin produced by polymerization of 20 to 95 parts by mass of monomer components comprising methyl methacrylate, an aromatic vinyl compound and a cyanidated vinyl compound in the presence of a rubbery polymer having a predetermined volume-average particle diameter, or comprises a mixture of the rubber-reinforced copolymeric resin and a copolymer of the above-mentioned monomer components. Additionally, the present anti-static resin composition comprises the above-mentioned rubber-reinforced resin and a polymer type anti-static agent, wherein the rubbery polymer is contained in an amount from 5% to 40% by mass. In each of the rubber-reinforced resin and the anti-static resin composition, the total amount of substances detected at a retention time of 10 to 24 minutes is 20,000 μg or less per gram of the sample as determined by pyrolysis GC analysis.