Provided is a gas barrier layered product including a base material and a layer stacked on at least one surface of the base material, wherein the layer is formed of a composition including: a hydrolyzed and condensed product of at least one compound (L) containing a metal atom to which at least one characteristic group selected from a halogen atom and an alkoxy group has been bonded, wherein the compound (L) contains at least one compound (A) and at least one compound (B), wherein a mole ratio of the compound (A) / the compound (B) is in a range of 0.5/99.5 to 40/60; and a neutralized product of a polymer containing at least one functional group selected from a carboxyl group and a carboxylic anhydride group, wherein at least 55 mol % of a —COO— group contained in the at least one functional group has been neutralized with a metal ion having a valence of two or more. Also provided is a method for producing the gas barrier layered product.