A resin composition which has oxygen-barrier properties less apt to depend on humidity and has high transparency; and a formed article and a film which include the resin composition are provided. The resin composition includes from 10 to 90 parts by mass of a polyamide resin (A) and from 90 to 10 parts by mass of a polyamide resin (B), wherein the polyamide resin (A) includes constituent units derived from a diamine and constituent units derived from a dicarboxylic acid, with 70 mol % or more of the constituent units derived from a diamine being derived from xylylenediamine and 90 mol % or more of the constituent units derived from a dicarboxylic acid being derived from adipic acid; the polyamide resin (B) includes constituent units derived from a diamine and constituent units derived from a dicarboxylic acid, 70 mol % or more of the constituent units derived from a diamine being derived from xylylenediamine, from 30 to 65 mol % of the constituent units derived from a dicarboxylic acid being derived from an α,ω-linear chain aliphatic dicarboxylic acid having from 4 to 20 carbons, and from 70 to 35 mol % of the constituent units derived from a dicarboxylic acid being derived from isophthalic acid.