Provided is a thermoplastic resin composition or adhesive coating that makes it possible to bond at adequate strength a cyclic polyolefin polymer and aluminum foil or another such metal or metal compound or an ethylene-vinyl alcohol copolymer. A thermoplastic resin composition consists of (A) 100 parts by mass of a thermoplastic resin; (B) 0.05-5 parts by mass of one or more selected from the group consisting of unsaturated carboxylic acids and unsaturated carboxylic acid derivatives; and (C) 0.01-3 parts by mass of an organic peroxide; and component (A) is (a1) 10-90 mass% of cyclic polyolefin polymer and (a2) 90-10 mass% of a hydrogenated block copolymer consisting of a polymer block composed mainly of an aromatic vinyl compound and a random copolymer block of a conjugated diene compoundand an aromatic vinyl compound (where the total of component (a1) and component (a2) is 100 mass%).