To provide a resin composition, preventing occurrence of lumps at fusion molding, having sufficient heat and light resistance, capable of obtaining molding bodies hard to become a microparticle plastic after disposal and having the above characteristics improved sufficiently compared to the same material using ethylene-vinyl alcohol copolymer (EVOH), and to provide the molded body and a multilayer structure using the above resin composition.SOLUTION: An objective resin composition includes EVOH (A) and aluminum ions (B), and at least part of EVOH (A) has at least one of a carboxylic acids unit (I) located at a polymer terminal and a lactone ring unit (II). In the composition, the total content (i+ii) per 1 g of EVOH (A) of the carboxylic acids unit (I) and lactone ring unit (II) is in the range of 14-78 μmol/g, and the content (b) per 1 g of EVOH (A) of the aluminum ion (B) is in the range of 0.002-0.17 μmol/g.SELECTED DRAWING: None